Recording apparatus and method, computer program, and recording medium

ABSTRACT

A recording apparatus ( 1 ) comprises a first calculating means ( 22 ) that calculates an optimum power to be used for recording a data pattern in a recording-scheduled area portion of a radially inner area ( 111 ); a first control means ( 22 ) that uses the optimum power to record a data pattern in an area portion radially outer than the recording-scheduled area portion; a second calculating means ( 22 ) that takes into account a difference between the recording sensitivity of the recording-scheduled area portion and the recording sensitivity of the area portion radially outer than the recording-scheduled area portion to calculate an adjustment power to be used for adjusting the recording condition in the area portion radially outer than the recording-scheduled area portion; a second control means ( 22 ) that records, in the area portion radially outer than the recording-scheduled area portion, a data pattern for adjusting the recording condition by use of the adjustment power; a reading means ( 12 ) that acquires a read signal; a measuring means ( 19 ) that measures the jitter of the read signal; an adjusting means ( 21 ) that adjusts the recording condition such that the jitter meets a desired condition; and a third control means ( 22 ) that uses the optimum power and adjusted recording condition to start the recording of the data pattern in the recording-scheduled area portion.

TECHNICAL FIELD

The present invention relates to a recording apparatus for and arecording method of recording a data pattern onto a recording medium, acomputer program which makes a computer function as such a recordingapparatus, and the recording medium.

BACKGROUND ART

Optical discs such as a DVD and a Blu-ray disc have been rapidly spread.In such optical discs, various technologies are suggested for OPC(Optimum Power Control) for providing an appropriate power(specifically, recording power) of a laser beam. For example, a patentdocument 1 discloses a technology of performing the OPC by judging therecording amount of data to be recorded on a recordable recording mediumwhich performs DAO (Disc At Once) and by recording an OPC pattern intoan area portion in which the data is not recorded. Moreover, a patentdocument 2 discloses a technology of predicting an optimum power whenthe data is recorded into an area between two PCAs (Power CalibrationAreas) from the result of the OPC performed in each of the PCA locatedon the innermost side of the optical disc and the PCA located on theoutermost side of the optical disc.

On the other hand, separately from the OPC, various technologies arealso disclosed for a recording compensation operation which is anoperation of providing an appropriate strategy of the laser beam (i.e.shape of a recording pulse). A patent document 3 discloses one exampleof the recording compensation operation.

Patent document 1: Japanese Patent Application Laid Open No. 2006-99889Patent document 2: Japanese Patent Publication No. 3765223Patent document 3: Japanese Patent Application Laid Open No. 2000-207742

DISCLOSURE OF INVENTION Subject to be Solved by the Invention

However, in the aforementioned recording compensation operation, inprinciple, the recording compensation operation is performed in the PCA(Power Calibration Area) located on the innermost side of the opticaldisc. Moreover, in the case of a relatively high linear velocity whichcannot be realized in the PCA located on the innermost side, generally,the recording compensation operation is performed in the PCA (PowerCalibration Area) located on the outermost side of the optical disc. Onthe other hand, it is a user data area located between the two PCAs thata data pattern is actually recorded. Here, in the optical disc (inparticular, a DVD-R or the like which is a recordable recording medium),a pigment film which is a recording film is generally formed by spincoating, so that it is considered that there are variations in recordingsensitivity of the recording film (in particular, between a recordingsensitivity in the PCA located on the outermost side and a recordingsensitivity in the user data area). Thus, even if the optimum power inthe user data area is predicted by the technology disclosed in thepatent document 2, the optimum power is not always optimal in the PCAlocated on the outermost side in which the recording compensationoperation is performed. Thus, if the recording compensation operation isperformed in the PCA located on the outermost side by merely using theoptimum power calculated by the OPC, the recording properties of thedata pattern in the user data area may deteriorate due to an influenceof the variations in recording sensitivity, which is technicallyproblematic.

In view of the aforementioned problems, it is therefore an object of thepresent invention to provide, for example, a recording apparatus andmethod which can more preferably optimize the strategy by performing therecording compensation operation in a more preferable aspect, as well asa computer program and a recording medium.

Means for Solving the Subject

The above object of the present invention can be achieved by a recordingapparatus provided with: a recording device for recording a desired datapattern onto a recording medium provided with an inner area and a userdata area located on an outer side of the inner area; a firstcalculating device for calculating an optimum power, which is used inrecording the data pattern into a recording-scheduled area portion,before the data pattern is recorded into the recording-scheduled areaportion which is an area portion in the user data area in which the datapattern is scheduled to be recorded by the recording device; a firstcontrolling device for controlling the recording device to record thedata pattern with the optimum power into an area portion which is outerthan an end on an outer side of the recording-scheduled area portion; asecond calculating device for calculating an adjustment power, which isused in adjusting a recording condition of the recording device in anarea portion which is outer than the end on the outer side of therecording-scheduled area portion, in consideration of a differencebetween a recording sensitivity in the recording-scheduled area portionand a recording sensitivity in the area portion which is outer than theend on the outer side of the recording-scheduled area portion, byreading the data pattern recorded by the control of the firstcontrolling device; a second controlling device for controlling therecording device to record the data pattern for adjusting the recordingcondition with the adjustment power into the area portion which is outerthan the end on the outer side of the recording-scheduled area portion;a reading device for reading the data pattern recorded by the control ofthe second controlling device, thereby obtaining a read signal; ameasuring device for measuring jitter of the read signal; an adjustingdevice for adjusting the recording condition such that the jittermeasured by the measuring device satisfies a desired condition; and athird controlling device for controlling the recording device to startthe recording of the data pattern into the recording-scheduled areaportion by using the optimum power and the recording condition adjustedby the adjusting device.

The above object of the present invention can be also achieved by arecording method in a recording apparatus provided with: a recordingdevice for recording a desired data pattern onto a recording mediumprovided with an inner area and a user data area located on an outerside of the inner area, the recording method provided with: a firstcalculating process of calculating an optimum power, which is used inrecording the data pattern into a recording-scheduled area portion,before the data pattern is recorded into the recording-scheduled areaportion which is an area portion in the user data area in which the datapattern is scheduled to be recorded by the recording device; a firstcontrolling process of controlling the recording device to record thedata pattern with the optimum power into an area portion which is outerthan an end on an outer side of the recording-scheduled area portion; asecond calculating process of calculating an adjustment power, which isused in adjusting a recording condition of the recording device in anarea portion which is outer than the end on the outer side of therecording-scheduled area portion, in consideration of a differencebetween a recording sensitivity in the recording-scheduled area portionand a recording sensitivity in the area portion which is outer than theend on the outer side of the recording-scheduled area portion, byreading the data pattern recorded by the control of the firstcontrolling process; a second controlling process of controlling therecording device to record the data pattern for adjusting the recordingcondition with the adjustment power into the area portion which is outerthan the end on the outer side of the recording-scheduled area portion;a reading process of reading the data pattern recorded by the control ofthe second controlling process, thereby obtaining a read signal; ameasuring process of measuring jitter of the read signal; an adjustingprocess of adjusting the recording condition such that the jittermeasured by the measuring process satisfies a desired condition; and athird controlling process of controlling the recording device to startthe recording of the data pattern into the recording-scheduled areaportion by using the optimum power and the recording condition adjustedby the adjusting process.

The above object of the present invention can be also achieved by acomputer program for recording control and for controlling a computerprovided in a recording apparatus provided with: a recording device forrecording a desired data pattern onto a recording medium provided withan inner area and a user data area located on an outer side of the innerarea; a first calculating device for calculating an optimum power, whichis used in recording the data pattern into a recording-scheduled areaportion, before the data pattern is recorded into therecording-scheduled area portion which is an area portion in the userdata area in which the data pattern is scheduled to be recorded by therecording device; a first controlling device for controlling therecording device to record the data pattern with the optimum power intoan area portion which is outer than an end on an outer side of therecording-scheduled area portion; a second calculating device forcalculating an adjustment power, which is used in adjusting a recordingcondition of the recording device in an area portion which is outer thanthe end on the outer side of the recording-scheduled area portion, inconsideration of a difference between a recording sensitivity in therecording-scheduled area portion and a recording sensitivity in the areaportion which is outer than the end on the outer side of therecording-scheduled area portion, by reading the data pattern recordedby the control of the first controlling device; a second controllingdevice for controlling the recording device to record the data patternfor adjusting the recording condition with the adjustment power into thearea portion which is outer than the end on the outer side of therecording-scheduled area portion; a reading device for reading the datapattern recorded by the control of the second controlling device,thereby obtaining a read signal; a measuring device for measuring jitterof the read signal; an adjusting device for adjusting the recordingcondition such that the jitter measured by the measuring devicesatisfies a desired condition; and a third controlling device forcontrolling the recording device to start the recording of the datapattern into the recording-scheduled area portion by using the optimumpower and the recording condition adjusted by the adjusting device, thecomputer program making the computer function as at least one portion ofthe recording device, the first calculating device, the firstcontrolling device, the second calculating device, the secondcontrolling device, the reading device, the measuring device, theadjusting device, and the third controlling device.

The above object of the present invention can be also achieved by afirst recording medium which is provided with an inner area and a userdata area located on an outer side of the inner area and on which a datapattern is recorded by a recording apparatus provided with: a recordingdevice for recording the desired data pattern onto the recording medium;a first calculating device for calculating an optimum power, which isused in recording the data pattern into a recording-scheduled areaportion, before the data pattern is recorded into therecording-scheduled area portion which is an area portion in the userdata area in which the data pattern is scheduled to be recorded by therecording device; a first controlling device for controlling therecording device to record the data pattern with the optimum power intoan area portion which is outer than an end on an outer side of therecording-scheduled area portion; a second calculating device forcalculating an adjustment power, which is used in adjusting a recordingcondition of the recording device in an area portion which is outer thanthe end on the outer side of the recording-scheduled area portion, inconsideration of a difference between a recording sensitivity in therecording-scheduled area portion and a recording sensitivity in the areaportion which is outer than the end on the outer side of therecording-scheduled area portion, by reading the data pattern recordedby the control of the first controlling device; a second controllingdevice for controlling the recording device to record the data patternfor adjusting the recording condition with the adjustment power into thearea portion which is outer than the end on the outer side of therecording-scheduled area portion; a reading device for reading the datapattern recorded by the control of the second controlling device,thereby obtaining a read signal; a measuring device for measuring jitterof the read signal; an adjusting device for adjusting the recordingcondition such that the jitter measured by the measuring devicesatisfies a desired condition; and a third controlling device forcontrolling the recording device to start the recording of the datapattern into the recording-scheduled area portion by using the optimumpower and the recording condition adjusted by the adjusting device.

The above object of the present invention can be also achieved by asecond recording medium provided with; an inner area; a user data arealocated on an outer side of the inner area; and a recording conditionrecording area to record therein a recording condition adjusted by arecording apparatus provided with: a recording device for recording adesired data pattern onto the recording medium; a first calculatingdevice for calculating an optimum power, which is used in recording thedata pattern into a recording-scheduled area portion, before the datapattern is recorded into the recording-scheduled area portion which isan area portion in the user data area in which the data pattern isscheduled to be recorded by the recording device; a first controllingdevice for controlling the recording device to record the data patternwith the optimum power into an area portion which is outer than an endon an outer side of the recording-scheduled area portion; a secondcalculating device for calculating an adjustment power, which is used inadjusting the recording condition of the recording device in an areaportion which is outer than the end on the outer side of therecording-scheduled area portion, in consideration of a differencebetween a recording sensitivity in the recording-scheduled area portionand a recording sensitivity in the area portion which is outer than theend on the outer side of the recording-scheduled area portion, byreading the data pattern recorded by the control of the firstcontrolling device; a second controlling device for controlling therecording device to record the data pattern for adjusting the recordingcondition with the adjustment power into the area portion which is outerthan the end on the outer side of the recording-scheduled area portion;a reading device for reading the data pattern recorded by the control ofthe second controlling device, thereby obtaining a read signal; ameasuring device for measuring jitter of the read signal; an adjustingdevice for adjusting the recording condition such that the jittermeasured by the measuring device satisfies a desired condition; and athird controlling device for controlling the recording device to startthe recording of the data pattern into the recording-scheduled areaportion by using the optimum power and the recording condition adjustedby the adjusting device.

The operation and other advantages of the present invention will becomemore apparent from the embodiments explained below.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram conceptually showing the basic structure of arecording apparatus in a first example.

FIG. 2 is a schematic plan view showing the basic structure of anoptical disc and a schematic conceptual view showing a recording areastructure in the radial direction of the optical disc.

FIG. 3 is a flowchart conceptually showing a flow of operations of therecording apparatus in the first example.

FIG. 4 are area structure diagrams conceptually showing an example ofsetting an area portion for performing a recording compensationoperation targeted at an optical disc in which a lead-in area ispre-recorded.

FIG. 5 are area structure diagrams conceptually showing an example ofsetting the area portion for performing the recording compensationoperation targeted at an optical disc in which the lead-in area is notpre-recorded.

FIG. 6 are area structure diagrams conceptually showing another exampleof setting the area portion for performing the recording compensationoperation.

FIG. 7 is a flowchart conceptually showing a flow of an operation ofcalculating the power of a laser beam for performing the recordingcompensation operation.

FIG. 8 are graphs conceptually showing recording properties in an areaportion (or a recording-scheduled area portion) in which a data patternis scheduled to be recorded of a data recording area and recordingproperties in an area portion (or a recording compensation area) inwhich the recording compensation operation is performed.

FIG. 9 is a flowchart conceptually showing a flow of the recordingcompensation operation in a step S109 in FIG. 3.

FIG. 10 is a waveform diagram conceptually showing an operation ofmeasuring jitter by an averaging circuit, on a read sample value series.

FIG. 11 is a block diagram conceptually showing the basic structure ofthe averaging circuit.

FIG. 12 is a graph conceptually showing the states of shift jittercomponents in respective data patterns and a shift jitter component as awhole before recording compensation and the states of shift jittercomponents in respective data patterns and a shift jitter component as awhole after the recording compensation.

FIG. 13 is a timing chart conceptually showing a first aspect of arecording strategy adjustment operation.

FIG. 14 is a timing chart conceptually showing a second aspect of therecording strategy adjustment operation.

FIG. 15 is a timing chart conceptually showing a third aspect of therecording strategy adjustment operation.

FIG. 16 is a graph conceptually showing total jitter of the datapatterns recorded without performing the recording compensationoperation and total jitter of the data pattern recorded after therecording compensation operation is performed in an aspect associatedwith the first example.

FIG. 17 is a graph conceptually showing the recording property in thecase where the recording compensation operation is performed aftercalculating an optimum power calculated by OPC without consideration ofa difference in recording sensitivity.

FIG. 18 is a graph conceptually showing the recording property in thecase where the recording compensation operation is performed aftercalculating a power for performing the recording compensation operationin consideration of the difference in recording sensitivity.

FIG. 19 a graph in which jitter and asymmetry are associated with theradial position of the optical disc.

FIG. 20 are graphs conceptually showing a relation between the presenceof a sensitivity change and the jitter and the asymmetry.

FIG. 21 are waveform diagrams conceptually showing the total jitter andasymmetry of the data pattern recorded by the recording apparatus whichdoes not perform the recording compensation operation and the totaljitter and asymmetry of the data pattern recorded by the recordingapparatus which has performed the recording compensation operation in anouter PCA, in association with the radial position of the optical disc.

FIG. 22 is a block diagram conceptually showing the basic structure ofan information recording apparatus in a second example.

FIG. 23 is a block diagram conceptually showing the basic structure ofan information recording apparatus in a third example.

DESCRIPTION OF REFERENCE CODES

-   1, 2, 3 recording apparatus-   10 spindle motor-   11 pickup-   12 HPF-   13 A/D converter-   14 pre-equalizer-   15 limit equalizer-   16 binary circuit-   17 decoding circuit-   18 delay circuit-   19 averaging circuit-   20 pattern judgment circuit-   21 recording strategy setting circuit-   22 CPU-   23 adder-   24 reference level detection device

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, as the best mode for carrying out the present invention, anexplanation will be given on embodiments of the recording apparatus andmethod, the computer program, and the recording medium of the presentinvention.

(Embodiment of Recording Apparatus)

An embodiment of the recording apparatus of the present invention is arecording apparatus provided with: a recording device for recording adesired data pattern onto a recording medium provided with an inner areaand a user data area located on an outer side of the inner area; a firstcalculating device for calculating an optimum power, which is used inrecording the data pattern into a recording-scheduled area portion,before the data pattern is recorded into the recording-scheduled areaportion which is an area portion in the user data area in which the datapattern is scheduled to be recorded by the recording device; a firstcontrolling device for controlling the recording device to record thedata pattern with the optimum power into an area portion which is outerthan an end on an outer side of the recording-scheduled area portion; asecond calculating device for calculating an adjustment power, which isused in adjusting a recording condition of the recording device in anarea portion which is outer than the end on the outer side of therecording-scheduled area portion, in consideration of a differencebetween a recording sensitivity in the recording-scheduled area portionand a recording sensitivity in the area portion which is outer than theend on the outer side of the recording-scheduled area portion, byreading the data pattern recorded by the control of the firstcontrolling device; a second controlling device for controlling therecording device to record the data pattern for adjusting the recordingcondition with the adjustment power into the area portion which is outerthan the end on the outer side of the recording-scheduled area portion;a reading device for reading the data pattern recorded by the control ofthe second controlling device, thereby obtaining a read signal; ameasuring device for measuring jitter of the read signal; an adjustingdevice for adjusting the recording condition such that the jittermeasured by the measuring device satisfies a desired condition; and athird controlling device for controlling the recording device to startthe recording of the data pattern into the recording-scheduled areaportion by using the optimum power and the recording condition adjustedby the adjusting device.

According to the embodiment of the recording apparatus of the presentinvention, by the operation of the recording device, the recordingmedium is irradiated with a laser beam or the like. As a result, thedata pattern according to the data to be recorded is recorded onto therecording medium.

Here, on the recording apparatus in the embodiment, an operationexplained below is performed before the operation of recording the datapattern performed by the recording device.

Firstly, by the operation of the first calculating device, the optimumpower of the laser beam used in recording the data pattern into therecording-scheduled area portion is calculated.

Then, the area portion which is outer than the end on the outer side ofthe recording-scheduled area portion (i.e. the area portion in the userdata area in which the data pattern according to the data to be recordedis not scheduled to be recorded) is irradiated with the laser beam withthe optimum power, and as a result, the data pattern is recorded.

Then, by the operation of the second calculating device, the datapattern recorded by the control of the first controlling device is read.The reading result directly or indirectly indicates the recordingsensitivity in the area portion which is outer than the end on the outerside of the recording-scheduled area portion (in other words, the areaportion in which the data pattern for adjusting the recording conditionis recorded and in which a recording compensation operation isperformed). On the other hand, the result of reading a data pattern fortest writing, recorded by the operation of the first calculating device,directly or indirectly indicates the recording sensitivity in therecording-scheduled area portion. Thus, the difference becomes clearbetween the recording sensitivity in the recording-scheduled areaportion and the recording sensitivity in the area portion in which therecording compensation operation is performed. The second calculatingdevice calculates the adjustment power used in adjusting the recordingcondition in the area portion which is outer than the end on the outerside of the recording-scheduled area portion, in consideration of thedifference in recording sensitivity.

Then, the recording compensation operation is actually performed.Specifically, firstly, by the control of the second controlling device,the area portion which is outer than the end on the outer side of therecording-scheduled area portion is irradiated with the laser beam withthe adjustment power, and as a result, the data pattern for adjustingthe recording condition of the recording device is recorded. In otherwords, the data pattern for adjusting the recording condition of therecording device is recorded into the area portion in the user data areain which the data pattern according to the data to be recorded is notscheduled to be recorded.

Then, the data pattern recorded in the area portion which is outer thanthe end on the outer side of the recording-scheduled area portion isread by the operation of the reading device. As a result, the readsignal is obtained. Then, by the operation of the measuring device, thejitter of the read signal is detected. Then, by the operation of theadjusting device, the recording condition of the recording device isadjusted such that the detected jitter satisfies the desired condition.

After the recording condition is adjusted, the recording of the datapattern into the user data area is actually started by the control ofthe third controlling device. In this case, the power of the laser beamis set to the optimum power calculated by the first calculating device,and the recording condition is set to the recording condition adjustedby the adjusting device.

By this, the jitter of the read signal obtained by reading the datapattern recorded after the adjustment of the recording conditionsatisfies the desired condition. Therefore, it is possible to improvethe reading quality of the read signal (in other words, recordingquality or reproduction quality).

In particular, in the embodiment, before the data pattern for adjustingthe recording condition is recorded (i.e. before the recordingcompensation operation is performed), the power of the laser beam iscorrected in consideration of the difference between the recordingsensitivity in the recording-scheduled area portion and the recordingsensitivity in the area portion in which the recording compensationoperation is performed.

Here, consideration is given to the operation of performing therecording compensation operation in the area portion which is outer thanthe end on the outer side of the recording-scheduled area portion (i.e.recording the data pattern for adjusting the recording condition) byusing the optimum power in the recording-scheduled area portion withoutconsideration of the difference in recording sensitivity. In this case,the optimum power in the recording-scheduled area portion is notnecessarily optimal in the area portion in which the recordingcompensation operation is performed. Thus, the recording compensationoperation is likely performed with the power which is not optimal in thearea portion in which the recording compensation operation is performed.This is not preferable from the viewpoint of preferable adjustment ofthe recording condition.

In the embodiment, however, the power of the laser beam for performingthe recording compensation operation is calculated in consideration ofthe difference in recording sensitivity as described above, so that therecording compensation operation is performed with the optimum power inthe area portion in which the recording compensation operation isperformed. On the other hand, when the data pattern according to thedata to be recorded is actually recorded into the user data area, theoptimum power calculated by the first calculating device and therecording condition adjusted by the adjusting device are used, so thatthe data pattern can be preferably recorded in the user data area. Inother words, the data pattern can be recorded without deteriorating therecording quality of the data pattern.

In addition, in the embodiment, the recording compensation operation canbe performed by recording the data pattern into the area portion whichis closer to the area portion in the user data area in which the datapattern is actually recorded (i.e. the recording-scheduled area portion)in comparison with the area portion such as a PCA disposed on theinnermost side or the outermost side. Thus, the properties (e.g. therecording sensitivity) of the area portion in which the recordingcompensation operation is performed are rarely far removed from theproperties (e.g. the recording sensitivity) of the area portion in whichthe data pattern according to the data to be recorded is actuallyrecorded. By this, in comparison with a case where the recordingcompensation operation is performed in the area portion such as a PCAdisposed on the innermost side or the outermost side, the recordingcondition optimized by the recording compensation operation is highlylikely preferable or optimal even in the area portion in which the datapattern is actually recorded. In other words, by performing therecording compensation operation in a more preferable aspect, it ispossible to optimize the recording condition, more preferably.Therefore, the data pattern can be preferably recorded into the userdata area by using the recording condition optimized by the recordingcompensation operation.

Incidentally, in the embodiment, due to the correction considering therecording sensitivity described above, even if the recording-scheduledarea portion and the recording compensation area are located away fromeach other, it is not considered to be particularly problematic.However, considering the fact that it is more preferable that theproperties in the recording-scheduled area portion are closer to theproperties in the recording compensation area, the recording-scheduledarea portion is preferably closer to the recording compensation area. Inthis regard, in the embodiment, it is possible to receive such a greateffect that the recording compensation operation can be performed, morepreferably.

Moreover, in the aforementioned background art (particularly, the patentdocument 3), a special data pattern for OPC is recorded. Thus,considering that bringing the area portion in which the special datapattern is recorded close to the recording-scheduled area portion maycause a runaway operation if a reproducing apparatus mistakenly readsthe special data pattern, it is not preferable. On the other hand,according to the embodiment, in order to perform the recordingcompensation operation, a normal data pattern is recorded. Thus, even ifthe reproducing apparatus reads the data pattern by bringing the areaportion in which the normal data pattern is recorded close to therecording-scheduled area portion, that does not cause the runwayoperation. Even in this regard, according to the embodiment, it ispossible to receive excellent effects in comparison with the backgroundart.

In one aspect of the embodiment of the recording apparatus of thepresent invention, the second calculating device calculates theadjustment power which allows optimum recording properties of the datapattern recorded by the control of the first controlling device.

According to this aspect, it is possible to perform the recordingcompensation operation with the adjustment power which is optimum in thearea portion in which the recording compensation operation is performed,in consideration of the difference between the recording sensitivity inthe recording-scheduled area portion and the recording sensitivity inthe area portion in which the recording compensation operation isperformed. Thus, it is possible to improve the recording quality of thedata pattern.

In another aspect of the embodiment of the recording apparatus of thepresent invention, the second calculating device calculates theadjustment power which absorbs (in other words, cancels) the differencebetween the recording sensitivity in the recording-scheduled areaportion and the recording sensitivity in the area portion which is outerthan the end on the outer side of the recording-scheduled area portion.

According to this aspect, it is possible to perform the recordingcompensation operation with the adjustment power which is optimum in thearea portion in which the recording compensation operation is performed,in consideration of the difference between the recording sensitivity inthe recording-scheduled area portion and the recording sensitivity inthe area portion in which the recording compensation operation isperformed. Thus, it is possible to improve the recording quality of thedata pattern which accords to the data to be recorded into the user dataarea and which is recorded with the optimum power.

In another aspect of the embodiment of the recording apparatus of thepresent invention, the first calculating device calculates the optimumpower, which is used in recording the data pattern at a first linearvelocity into the recording-scheduled area portion, by controlling therecording device to record the data pattern for test writing at a secondlinear velocity, which is lower than the first linear velocity, in theinner area before the data pattern is recorded at the first linearvelocity into the recording-scheduled area portion, the firstcontrolling device controls the recording device to record the datapattern with the optimum power and at the first linear velocity into thearea portion which is outer than the end on the outer side of therecording-scheduled area portion, the second calculating devicecalculates the adjustment power, which is used in adjusting therecording condition of the recording device at the first linear velocityin the area portion which is outer than the end on the outer side of therecording-scheduled area portion, in consideration of the differencebetween the recording sensitivity in the recording-scheduled areaportion and the recording sensitivity in the area portion which is outerthan the end on the outer side of the recording-scheduled area portion,by reading the data pattern recorded by the control of the firstcontrolling device, the second controlling device controls the recordingdevice to record the data pattern for adjusting the recording conditionwith the adjustment power and at the first linear velocity into the areaportion which is outer than the end on the outer side of therecording-scheduled area portion, and the third controlling devicecontrols the recording device to start the recording of the data patterninto the recording-scheduled area portion at the first linear velocityby using the optimum power and the recording condition adjusted by theadjusting device.

According to this aspect, firstly, by the operation of the firstcalculating device, the optimum power of the laser beam used inrecording the data pattern into the recording-scheduled area portion atthe first linear velocity is calculated on the basis of the data patternfor test writing recorded in the inner area at the second linearvelocity. In other words, by recording the data pattern for test writingat the second linear velocity which can be realized in the inner area,instead of the first linear velocity which cannot be realized in theinner area, the optimum power used in recording the data pattern intothe recording-scheduled area at the first linear velocity is calculated.

Here, the first calculating device may predict or estimate the optimumpower used at the first linear velocity which cannot be realized in theinner area, on the basis of the result of reading the data pattern fortest writing recorded at the second linear velocity which can berealized in the inner area. In this case, as described later, the datapattern for test writing may be recorded by using a special recordingstrategy (i.e. recording condition) which allows the aforementionedprediction operation. Alternatively, the optimum power in the areaportion other than the inner area may be predicted by interpolation onthe basis of a correlation between the recording quality of the datapattern for test writing and the recording power.

Then, by the control of the first controlling device, the area portionwhich is outer than the end on the outer side of the recording-scheduledarea portion (i.e. the area portion in the user data area in which thedata pattern according to the data to be recorded is not scheduled to berecorded) is irradiated with the laser beam with the optimum power atthe first linear velocity, and as a result, the data pattern isrecorded.

Then, by the operation of the second calculating device, the adjustmentpower used in adjusting the recording condition at the first linearvelocity in the area portion which is outer than the end on the outerside of the recording-scheduled area portion is calculated inconsideration of the difference in recording sensitivity.

Then, the recording compensation operation is actually performed.Specifically, firstly, by the control of the second controlling device,the area portion which is outer than the end on the outer side of therecording-scheduled area portion is irradiated with the laser beam withthe adjustment power at the first linear velocity, and as a result, thedata pattern for adjusting the recording condition of the recordingdevice is recorded. In other words, the data pattern for adjusting therecording condition of the recording device is recorded into the areaportion in the user data area in which the data pattern according to thedata to be recorded is not scheduled to be recorded.

Then, by the operation of the reading device, the data pattern recordedin the area portion which is outer than the end on the outer side of therecording-scheduled area portion is read. As a result, the read signalis obtained. Then, by the operation of the measuring device, the jitterof the read signal is detected. Then, by the operation of the adjustingdevice, the recording condition of the recording device is adjusted suchthat the detected jitter satisfies the desired condition.

After the adjustment of the recording condition, by the control of thethird controlling device, the recording of the data pattern according tothe data to be recorded into the user data area at the first linearvelocity is started. In this case, the power of the laser beam is set tothe optimum power calculated by the first calculating device, and therecording condition is set to the recording condition adjusted by theadjusting device.

In this aspect, the first calculating device may calculate the optimumpower if the data pattern for adjusting the recording condition at thefirst linear velocity cannot be recorded into the inner area, the firstcontrolling device may control the recording device to record the datapattern with the optimum power and at the first linear velocity into thearea portion which is outer than the end on the outer side of therecording-scheduled area portion if the data pattern for adjusting therecording condition at the first linear velocity cannot be recorded intothe inner area, the second calculating device may calculate theadjustment power if the data pattern for adjusting the recordingcondition at the first linear velocity cannot be recorded into the innerarea, and the second controlling device may control the recording deviceto record the data pattern for adjusting the recording condition withthe adjustment power and at the first linear velocity into the areaportion which is outer than the end on the outer side of therecording-scheduled area portion if the data pattern for adjusting therecording condition at the first linear velocity cannot be recorded intothe inner area.

By virtue of such construction, in the case of a relatively high linearvelocity which cannot be realized in the inner area disposed on theinner side (e.g. PCA), it is possible to perform the recordingcompensation operation in the area portion which is closer to the areaportion in the user data area in which the data pattern according to thedata to be recorded is actually recorded (i.e. the recording-scheduledarea portion), instead of performing the recording compensationoperation in an outer area disposed on the outermost side. Thiseliminates a need to perform the recording compensation operation in thearea portion on the outermost side in which the recording properties mayvary widely. As described above, by performing the recordingcompensation operation in a more preferable aspect, it is possible tooptimize the recording condition, more preferably.

In another aspect of the embodiment of the recording apparatus of thepresent invention, it is further provided with: an amplitude limitfiltering device for limiting an amplitude level of the read signal byusing a predetermined amplitude limit value, thereby obtaining anamplitude limit signal and for performing a high-frequency emphasisfiltering process on the amplitude limit signal, thereby obtaining anequalization-corrected signal; and a detecting device for detecting thedata pattern of the equalization-corrected signal, the measuring devicemeasuring jitter of the equalization-corrected signal, the adjustingdevice adjusting the recording condition such that the jitter measuredby the measuring device satisfies a desired condition, with reference tothe data pattern detected by the detecting device.

According to this aspect, by the operation of the amplitude limitfiltering device, the amplitude level of the read signal is limited.Specifically, in a signal component of the read signal whose amplitudelevel is greater than an upper limit of the amplitude limit value orwhose amplitude level is less than a lower limit of the amplitude limitvalue, its amplitude level is limited to the upper limit or the lowerlimit of the amplitude limit value. On the other hand, in a signalcomponent of the read signal whose amplitude level is less than or equalto the upper limit of the amplitude limit value or whose amplitude levelis greater than or equal to the lower limit of the amplitude limitvalue, its amplitude level is not limited. As described above, the readsignal whose amplitude level is limited is referred to as the amplitudelimit signal. Moreover, the amplitude limit filtering device performsthe high-frequency emphasis filtering process on the amplitude limitsignal. As a result, the equalization-corrected signal is obtained inwhich the shortest data pattern included in the read signal (e.g. thedata pattern with a run length of 3T if the information recording mediumis a DVD, and the data pattern with a run length of 2T if theinformation recording medium is a Blu-ray Disc) has an emphasizedamplitude level. In other words, the amplitude limit filtering deviceperforms the same operation as a so-called limit equalizer, on the readsignal.

Then, by the operation of the measuring device, the jitter of theequalization-corrected signal is measured, instead of measuring thejitter of the read signal. In other words, in this aspect, instead ofdirectly using the read signal obtained by reading the data pattern fromthe recording medium to measure the jitter, the equalization-correctedsignal obtained by performing the amplitude limit process and thehigh-frequency emphasis filtering process on the read signal is used tomeasure the jitter.

Moreover, by the operation of the detecting device, the data pattern ofthe equalization-corrected signal is detected. More specifically, it isdetected which run length the data pattern of the equalization-correctedsignal has. The detected data pattern is referred to in the operation ofadjusting the recording condition by the adjusting device.

As described above, the data pattern is detected from theequalization-corrected signal in which the amplitude level of theshortest data pattern is emphasized by the operation of the amplitudelimit filtering device (i.e. limit equalizer). Thus, in any state of theasymmetry of the read signal, it is possible to preferably prevent sucha disadvantage that the shortest data pattern included in the readsignal does not cross a zero level. As a result, the shortest datapattern can be preferably detected. Thus, it is possible to preferablyadjust the recording condition for recording the shortest data pattern.By this, the recording compensation operation can be preferablyperformed with reference to the read signal including the shortest datapattern. In other words, regardless of the state of the asymmetry in theread signal before the recording compensation, the recordingcompensation operation can be preferably performed.

In another aspect of the embodiment of the recording apparatus of thepresent invention, it is further provided with an adding device foradding a predetermined offset signal to the read signal, therebyobtaining an offset-added signal, the measuring device measuring thejitter of the offset-added signal.

According to this aspect, the jitter of the offset-added signal ismeasured. Incidentally, for the offset signal, it is preferable to set asignal which allows the asymmetry of the read signal after the recordingcompensation operation to have a desired value, as occasion demands.Thus, in accordance with the addition of the offset signal, it ispossible to set the asymmetry of the read signal after the recordingcompensation, regardless of the state of the asymmetry before therecording compensation.

In another aspect of the embodiment of the recording apparatus of thepresent invention, the measuring device measures, as the jitter, a shiftjitter component caused by a state of the recorded data pattern fromamong the jitter, and the adjusting device adjusts the recordingcondition such that the shift jitter component as the jitter satisfiesthe desired condition.

According to this aspect, not the random jitter component, which ishardly predicted or which cannot be predicted, but the shift jittercomponent caused by the state of the data pattern which depends on therecording condition is measured. Therefore, by adjusting the recordingcondition, it is possible to preferably perform the recordingcompensation operation such that the shift jitter component satisfiesthe desired condition, relatively easily.

In an aspect of the recording apparatus in which the recording conditionis adjusted such that the shift jitter component satisfies the desiredcondition, as described above, a state in which the jitter satisfies thedesired condition may be a state in which the shift jitter component isless than or equal to a first predetermined value.

By virtue of such construction, it is possible to preferably perform therecording compensation operation so as to reduce the shift jittercomponent.

In an aspect of the recording apparatus in which the recording conditionis adjusted such that the shift jitter component satisfies the desiredcondition, as described above, a state in which the jitter satisfies thedesired condition is a state in which the shift jitter components in aplurality of types of respective data patterns with different runlengths may be substantially same to each other.

By virtue of such construction, it is possible to match the shift jittercomponents in a plurality of types of respective data patterns (e.g. 10types of data patterns with run lengths of 3T to 11T and 14T if theinformation recording medium is a DVD, and 7 types of data patterns withrun lengths of 2T to 9T if the information recording medium is a Blu-rayDisc). In other words, instead of narrowing jitter distributions in therespective data patterns, it is possible to match the average values ofthe jitter distributions in the respective data patterns (i.e. the shiftjitter components). By this, it is possible to perform the recordingcompensation operation which reduces the jitter, preferably andrelatively easily.

In an aspect of the recording apparatus in which the recording conditionis adjusted such that the shift jitter component satisfies the desiredcondition, as described above, a state in which the jitter satisfies thedesired condition may be a state in which a ratio of a random jittercomponent, which is caused by a noise from among the jitter, to thejitter is greater than or equal to a second predetermined value.

The jitter is indicated by the square root of a sum of the square of therandom jitter component and the square of the shift jitter component.Thus, if the random jitter component is greater than the shift jittercomponent (i.e. if the ratio of the random jitter component to thejitter is relatively large), the jitter is hardly reduced even if theshift jitter component is reduced. Therefore, by virtue of suchconstruction, it is possible to perform the recording compensationoperation such that a jitter-reduction effect is preferably achieved bythe adjustment of the recording condition. In other words, it ispossible to preferably avoid the inefficient recording compensationoperation in which the jitter-reduction effect is not preferablyachieved by the adjustment of the recording condition.

In an aspect of the recording apparatus in which the recording conditionis adjusted such that the shift jitter component satisfies the desiredcondition, as described above, the measuring device may measure, as theshift jitter component, an average value in each data pattern of samplevalues of the read signal or the equalization-corrected signal which isthe closest to a zero level point

By virtue of such construction, it is possible to measure the shiftjitter component, preferably and relatively easily.

In an aspect of the recording apparatus in which the recording conditionis adjusted such that the shift jitter component satisfies the desiredcondition, as described above, the adjusting device may preferentiallyadjust the recording condition in recording the data pattern having therelatively large shift jitter component out of a plurality of type ofthe data patterns with different run lengths.

By virtue of such construction, it is possible to reduce the jitter moreefficiently, in comparison with the construction that the recordingcondition in each data pattern is randomly adjusted.

In another aspect of the embodiment of the recording apparatus of thepresent invention, the recording device applies a laser beam, therebyrecording the data pattern, and the recording condition is at least oneof an amplitude and a pulse width of the laser beam or a driving pulsefor driving the laser beam.

By virtue of such construction, it is possible to preferably perform therecording compensation operation by adjusting the amplitude and thepulse width of the driving pulse or the laser beam.

In another aspect of the embodiment of the recording apparatus of thepresent invention, the recording device records the recording conditionadjusted by the adjusting device. In this case, the recording conditionis preferably recorded in association with identification informationfor identifying the information recording apparatus.

According to this aspect, the identification information about therecording apparatus and the recording condition are recorded on therecording medium. Thus, by reading the recording condition, whichcorresponds to the identification information about the recordingapparatus, from the recording medium and by using it as the recordingcondition of the recording device when the data pattern is recorded bythe recording apparatus, it is possible to receive the same variouseffects as those described above, in the recording operation performedon the recording medium, without adjusting the recording conditionagain.

Moreover, even if the recording condition is not recorded on therecording medium for the reason that the recording medium is blank orthe like, in the embodiment, it is possible to preferably perform therecording compensation operation. Moreover, if the resulting recordingcondition is recorded on the recording medium in association with theidentification information about the recording apparatus, it is possibleto receive the same various effects as those described above, in therecording performed on the recording medium, without adjusting therecording condition again next time the data pattern is recorded.

In other words, according to this aspect, without adjusting therecording condition by the adjusting device or with the recordingcondition adjusted at least once, it is possible to receive the samevarious effects as those described above, in the recording performed onthe recording medium, without adjusting the recording condition on thecorresponding recording apparatus again.

(Embodiment of Recording Method)

An embodiment of the recording method of the present invention is arecording method in a recording apparatus provided with: a recordingdevice for recording a desired data pattern onto a recording mediumprovided with an inner area and a user data area located on an outerside of the inner area, the recording method provided with: a firstcalculating process of calculating an optimum power, which is used inrecording the data pattern into a recording-scheduled area portion,before the data pattern is recorded into the recording-scheduled areaportion which is an area portion in the user data area in which the datapattern is scheduled to be recorded by the recording device; a firstcontrolling process of controlling the recording device to record thedata pattern with the optimum power into an area portion which is outerthan an end on an outer side of the recording-scheduled area portion; asecond calculating process of calculating an adjustment power, which isused in adjusting a recording condition of the recording device in anarea portion which is outer than the end on the outer side of therecording-scheduled area portion, in consideration of a differencebetween a recording sensitivity in the recording-scheduled area portionand a recording sensitivity in the area portion which is outer than theend on the outer side of the recording-scheduled area portion, byreading the data pattern recorded by the control of the firstcontrolling process; a second controlling process of controlling therecording device to record the data pattern for adjusting the recordingcondition with the adjustment power into the area portion which is outerthan the end on the outer side of the recording-scheduled area portion;a reading process of reading the data pattern recorded by the control ofthe second controlling process, thereby obtaining a read signal; ameasuring process of measuring jitter of the read signal; an adjustingprocess of adjusting the recording condition such that the jittermeasured by the measuring process satisfies a desired condition; and athird controlling process of controlling the recording device to startthe recording of the data pattern into the recording-scheduled areaportion by using the optimum power and the recording condition adjustedby the adjusting process.

According to the embodiment of the recording method of the presentinvention, it is possible to receive the same various effects as thosethat can be received by the aforementioned embodiment of the recordingapparatus of the present invention.

Incidentally, in response to the various aspects in the aforementionedembodiment of the recording apparatus of the present invention, theembodiment of the recording method of the present invention can alsoadopt various aspects.

(Embodiment of Computer Program)

An embodiment of the computer program of the present invention is acomputer program for recording control and for controlling a computerprovided in a recording apparatus provided with: a recording device forrecording a desired data pattern onto a recording medium provided withan inner area and a user data area located on an outer side of the innerarea; a first calculating device for calculating an optimum power, whichis used in recording the data pattern into a recording-scheduled areaportion, before the data pattern is recorded into therecording-scheduled area portion which is an area portion in the userdata area in which the data pattern is scheduled to be recorded by therecording device; a first controlling device for controlling therecording device to record the data pattern with the optimum power intoan area portion which is outer than an end on an outer side of therecording-scheduled area portion; a second calculating device forcalculating an adjustment power, which is used in adjusting a recordingcondition of the recording device in an area portion which is outer thanthe end on the outer side of the recording-scheduled area portion, inconsideration of a difference between a recording sensitivity in therecording-scheduled area portion and a recording sensitivity in the areaportion which is outer than the end on the outer side of therecording-scheduled area portion, by reading the data pattern recordedby the control of the first controlling device; a second controllingdevice for controlling the recording device to record the data patternfor adjusting the recording condition with the adjustment power into thearea portion which is outer than the end on the outer side of therecording-scheduled area portion; a reading device for reading the datapattern recorded by the control of the second controlling device,thereby obtaining a read signal; a measuring device for measuring jitterof the read signal; an adjusting device for adjusting the recordingcondition such that the jitter measured by the measuring devicesatisfies a desired condition; and a third controlling device forcontrolling the recording device to start the recording of the datapattern into the recording-scheduled area portion by using the optimumpower and the recording condition adjusted by the adjusting device (i.e.the embodiment of the recording apparatus of the present inventiondescribed above (including its various aspects)), the computer programmaking the computer function as at least one portion of the recordingdevice, the first calculating device, the first controlling device, thesecond calculating device, the second controlling device, the readingdevice, the measuring device, the adjusting device, and the thirdcontrolling device.

According to the embodiment of the computer program of the presentinvention, the aforementioned embodiment of the recording apparatus ofthe present invention can be relatively easily realized as a computerreads and executes the computer program from a program storage device,such as a ROM, a CD-ROM, a DVD-ROM, and a hard disk, or as it executesthe computer program after downloading the program through acommunication device.

Incidentally, in response to the various aspects in the aforementionedembodiment of the recording apparatus of the present invention, theembodiment of the computer program of the present invention can alsoadopt various aspects.

An embodiment of the computer program product of the present inventionis a computer program product in a computer-readable medium for tangiblyembodying a program of instructions executable by a computer provided ina recording apparatus provided with: a recording device for recording adesired data pattern onto a recording medium provided with an inner areaand a user data area located on an outer side of the inner area; a firstcalculating device for calculating an optimum power, which is used inrecording the data pattern into a recording-scheduled area portion,before the data pattern is recorded into the recording-scheduled areaportion which is an area portion in the user data area in which the datapattern is scheduled to be recorded by the recording device; a firstcontrolling device for controlling the recording device to record thedata pattern with the optimum power into an area portion which is outerthan an end on an outer side of the recording-scheduled area portion; asecond calculating device for calculating an adjustment power, which isused in adjusting a recording condition of the recording device in anarea portion which is outer than the end on the outer side of therecording-scheduled area portion, in consideration of a differencebetween a recording sensitivity in the recording-scheduled area portionand a recording sensitivity in the area portion which is outer than theend on the outer side of the recording-scheduled area portion, byreading the data pattern recorded by the control of the firstcontrolling device; a second controlling device for controlling therecording device to record the data pattern for adjusting the recordingcondition with the adjustment power into the area portion which is outerthan the end on the outer side of the recording-scheduled area portion;a reading device for reading the data pattern recorded by the control ofthe second controlling device, thereby obtaining a read signal; ameasuring device for measuring jitter of the read signal; an adjustingdevice for adjusting the recording condition such that the jittermeasured by the measuring device satisfies a desired condition; and athird controlling device for controlling the recording device to startthe recording of the data pattern into the recording-scheduled areaportion by using the optimum power and the recording condition adjustedby the adjusting device (i.e. the embodiment of the recording apparatusof the present invention described above (including its variousaspects)), the computer program product making the computer function asat least one portion of the recording device, the first calculatingdevice, the first controlling device, the second calculating device, thesecond controlling device, the reading device, the measuring device, theadjusting device, and the third controlling device.

According to the embodiment of the computer program product of thepresent invention, the aforementioned embodiment of the recordingapparatus of the present invention can be embodied relatively readily,by loading the computer program product from a recording medium forstoring the computer program product, such as a ROM (Read Only Memory),a CD-ROM (Compact Disc-Read Only Memory), a DVD-ROM (DVD Read OnlyMemory), a hard disk or the like, into the computer, or by downloadingthe computer program product, which may be a carrier wave, into thecomputer via a communication device. More specifically, the computerprogram product may include computer readable codes to cause thecomputer (or may comprise computer readable instructions for causing thecomputer) to function as the aforementioned embodiment of the recordingapparatus of the present invention.

Incidentally, in response to the various aspects in the aforementionedembodiment of the recording apparatus of the present invention, theembodiment of the computer program product of the present invention canalso employ various aspects.

(Embodiment of Recording Medium)

A first embodiment of the recording medium of the present invention is arecording medium which is provided with an inner area and a user dataarea located on an outer side of the inner area and on which a datapattern is recorded by a recording apparatus provided with: a recordingdevice for recording the desired data pattern onto the recording medium;a first calculating device for calculating an optimum power, which isused in recording the data pattern into a recording-scheduled areaportion, before the data pattern is recorded into therecording-scheduled area portion which is an area portion in the userdata area in which the data pattern is scheduled to be recorded by therecording device; a first controlling device for controlling therecording device to record the data pattern with the optimum power intoan area portion which is outer than an end on an outer side of therecording-scheduled area portion; a second calculating device forcalculating an adjustment power, which is used in adjusting a recordingcondition of the recording device in an area portion which is outer thanthe end on the outer side of the recording-scheduled area portion, inconsideration of a difference between a recording sensitivity in therecording-scheduled area portion and a recording sensitivity in the areaportion which is outer than the end on the outer side of therecording-scheduled area portion, by reading the data pattern recordedby the control of the first controlling device; a second controllingdevice for controlling the recording device to record the data patternfor adjusting the recording condition with the adjustment power into thearea portion which is outer than the end on the outer side of therecording-scheduled area portion; a reading device for reading the datapattern recorded by the control of the second controlling device,thereby obtaining a read signal; a measuring device for measuring jitterof the read signal; an adjusting device for adjusting the recordingcondition such that the jitter measured by the measuring devicesatisfies a desired condition; and a third controlling device forcontrolling the recording device to start the recording of the datapattern into the recording-scheduled area portion by using the optimumpower and the recording condition adjusted by the adjusting device.

A second embodiment of the recording medium of the present invention isa recording medium provided with: an inner area; a user data arealocated on an outer side of the inner area; and a recording conditionrecording area to record therein a recording condition adjusted by arecording apparatus provided with; a recording device for recording adesired data pattern onto the recording medium; a first calculatingdevice for calculating an optimum power, which is used in recording thedata pattern into a recording-scheduled area portion, before the datapattern is recorded into the recording-scheduled area portion which isan area portion in the user data area in which the data pattern isscheduled to be recorded by the recording device; a first controllingdevice for controlling the recording device to record the data patternwith the optimum power into an area portion which is outer than an endon an outer side of the recording-scheduled area portion; a secondcalculating device for calculating an adjustment power, which is used inadjusting the recording condition of the recording device in an areaportion which is outer than the end on the outer side of therecording-scheduled area portion, in consideration of a differencebetween a recording sensitivity in the recording-scheduled area portionand a recording sensitivity in the area portion which is outer than theend on the outer side of the recording-scheduled area portion, byreading the data pattern recorded by the control of the firstcontrolling device; a second controlling device for controlling therecording device to record the data pattern for adjusting the recordingcondition with the adjustment power into the area portion which is outerthan the end on the outer side of the recording-scheduled area portion;a reading device for reading the data pattern recorded by the control ofthe second controlling device, thereby obtaining a read signal; ameasuring device for measuring jitter of the read signal; an adjustingdevice for adjusting the recording condition such that the jittermeasured by the measuring device satisfies a desired condition; and athird controlling device for controlling the recording device to startthe recording of the data pattern into the recording-scheduled areaportion by using the optimum power and the recording condition adjustedby the adjusting device. In this case, the recording condition ispreferably recorded in association with identification information foridentifying the information recording apparatus.

According to the embodiments of the recording medium of the presentinvention, the identification information about the recording apparatusand the recording condition are recorded on the recording medium. Thus,by reading the recording condition, which corresponds to theidentification information about the recording apparatus, from therecording medium and by using it as the recording condition of therecording device when the data pattern is recorded by the recordingapparatus, it is possible to receive the same various effects as thosedescribed above, in the recording operation performed on the recordingmedium, without adjusting the recording condition again.

Moreover, even if the recording condition is not recorded on therecording medium for the reason that the recording medium is blank orthe like, in the embodiment, it is possible to preferably perform therecording compensation operation, as described above. Moreover, if theresulting recording condition is recorded on the recording medium inassociation with the identification information about the recordingapparatus, it is possible to receive the same various effects as thosedescribed above, in the recording performed on the recording medium,without adjusting the recording condition again next time the datapattern is recorded.

In other words, according to this aspect without adjusting the recordingcondition by the adjusting device or with the recording conditionadjusted at least once, it is possible to receive the same variouseffects as those described above, in the recording performed on therecording medium, without adjusting the recording condition on thecorresponding recording apparatus again.

Incidentally, the recording condition may be recorded in advance on therecording medium, or it may be recorded along with the recordingoperation, as occasion demands.

Incidentally, in response to the various aspects in the aforementionedembodiment of the recording apparatus of the present invention, each ofthe embodiments of the recording medium of the present invention canalso employ various aspects.

The operation and other advantages of the present invention will becomemore apparent from the examples explained below.

As explained above, according to the embodiment of the recordingapparatus of the present invention, it is provided with the recordingdevice, the first calculating device, the first controlling device, thesecond calculating device, the second controlling device, the readingdevice, the measuring device, the adjusting device, and the thirdcontrolling device. According to the embodiment of the recording methodof the present invention, it is provided with the first calculatingprocess, the first controlling process, the second calculating process,the second controlling process, the reading process, the measuringprocess, the adjusting process, and the third controlling process.According to the embodiment of the computer program of the presentinvention, it makes a computer function as the embodiment of therecording apparatus of the present invention. According to each of theembodiments of the recording medium of the present invention, it isprovided with the recording condition recording area in which the datapattern is recorded by the aforementioned recording apparatus or whichis to record therein the recording condition adjusted by theaforementioned adjusting device. Therefore, by performing the recordingcompensation operation in a more preferable aspect, it is possible tooptimize the strategy, more preferably.

EXAMPLES

Hereinafter, examples of the present invention will be described withreference to the drawings.

(1) First Example

Firstly, with reference to FIG. 1 to FIG. 21, a first example of therecording apparatus of the present invention will be explained.

(1-1) Basic Structure

Firstly, with reference to FIG. 1, the basic structure of a recordingapparatus in the first example will be described. FIG. 1 is a blockdiagram conceptually showing the basic structure of a recordingapparatus 1 in the first example.

As shown in FIG. 1, the recording apparatus 1 in the first example isprovided with a spindle motor 10, a pickup (PU) 11, a HPF (High PassFilter) 12, an A/D converter 13, a pre-equalizer 14, a binary circuit16, a decoding circuit 17, a delay circuit 18, an averaging circuit 19,a pattern judgment circuit 20, a recording strategy adjustment circuit21, and a CPU 22.

The pickup 11 constitutes one specific example of the “recording device”and the “reading device” of the present invention. The pickup 11photoelectrically converts reflected light when a laser beam LB isapplied to a recording surface of an optical disc 100 rotated by thespindle motor 10, thereby generating a read signal R_(RF). Moreover, thepickup 11 irradiates the recording surface of the optical disc 100 withthe laser beam LB according to a recording strategy set on the recordingstrategy setting circuit 21, thereby recording a data pattern onto theoptical disc 100.

The HPF 12 removes a low-frequency component of the read signal R_(RF)outputted from the pickup 11, and it outputs a resulting read signalR_(HC) to the A/D converter 13.

The A/D converter 13 samples the read signal R_(RF) in accordance with asampling clock outputted from a PLL (Phased Lock Loop) not illustratedor the like, and it outputs a resulting read sample value series RS tothe pre-equalizer 14.

The pre-equalizer 14 removes intersymbol interference which is based ontransmission characteristics in an information reading system which isformed of the pickup 11 and the optical disc 100, and it outputs aresulting read sample value series RS_(C) to each of the binary circuit16 and the delay circuit 18.

The binary circuit 16 performs a binary process on the read sample valueseries RS_(C), and it outputs a resulting binary signal to each of thedecoding circuit 17 and the pattern judgment circuit 19.

The decoding circuit 17 performs a decoding process or the like on thebinary signal, and it outputs a resulting reproduction signal toexternal reproduction equipment such as a display and a speaker. As aresult, data according to the data pattern recorded on the optical disc100 (e.g. video data, audio data, and the like) is reproduced.

The delay circuit 18 applies a delay corresponding to a time requiredfor the processes of the binary circuit 16 and the pattern judgmentcircuit 20 to the read sample value series RS_(C), and then, it outputsthe read sample value series RS_(C) to the averaging circuit 19. Inother words, by the operations of the delay circuit 18, each samplevalue in the read sample value series RS_(C) outputted from thepre-equalizer 14 is inputted to the averaging circuit 19 in the sametiming as the timing in which the data pattern judgment result of thesample value is inputted.

The averaging circuit 19 constitutes one specific example of the“measuring device” of the present invention. The averaging circuit 19measures the jitter of the read sample value series RS_(C). The detailsof the averaging circuit 19 will be detailed later (refer to FIG. 9).

The pattern judgment circuit 20 constitutes one specific example of the“detecting device” of the present invention. The pattern judgmentcircuit 20 judges the data pattern on the basis of the binary signaloutputted from the binary circuit 16. Namely, it judges which datapattern the binary signal inputted to the pattern judgment circuit 20is. The judgment result is outputted to the averaging circuit 19.

The recording strategy adjustment circuit 21 constitutes one specificexample of the “adjusting device” of the present invention. Therecording strategy adjustment circuit 21 adjusts the recording strategyof each data pattern on the basis of the jitter measured on theaveraging circuit 19.

The CPU 22 constitutes one specific example of the “first controllingdevice”, the “second controlling device”, the “third controllingdevice”, the “first calculating device”, and the “second calculatingdevice” of the present invention. The CPU 22 controls the aforementionedvarious constituents which constitute the recording apparatus 1, therebycontrolling the operations of the recording apparatus 1 as a whole.

(1-2) Optical Disc

Next, with reference to FIG. 2, an explanation will be given on thebasic structure of the optical disc 100 which is the target of therecording operation of the recording apparatus 1 in the first example.FIG. 2 is a schematic plan view showing the basic structure of theoptical disc 100 and a schematic conceptual view showing a recordingarea structure in the radial direction of the optical disc 100.

As shown in FIG. 2, the optical disc 100 has a recording surface on adisc main body, for example, with a diameter of about 12 cm as in a DVD.On the recording surface, the optical disc 100 is provided with a centerhole 101 as the center; an inner PCA (Power Calibration Area) 111 whichconstitutes one specific example of the “inner area” of the presentinvention; a RMA (Recording Management Area) 112; a lead-in area 118; adata recording area 114 which constitutes one specific example of the“user data area” of the present invention; a lead-out area 115; and anouter PCA 116. Moreover, for example, a groove track and a land trackare alternatively provided, spirally or concentrically, centered on thecenter hole 101. Moreover, on the track, the data pattern is divided andrecorded by a unit of ECC block. The ECC block is an error-correctabledata management unit. Moreover, in the example, the optical disc 100 ispreferably a recordable recording medium which can record the datapattern only once.

Then, the groove track is oscillated with a constant amplitude and at aconstant spatial frequency. In other words, the groove track is wobbled,and the cycle of the wobble is set to a predetermined value. On the landtrack, a pit referred to as a land pre-pit (LPP) is formed whichindicates a pre-format address. By virtue of the two addressing (i.e.the wobble and the land pre-pit), it is possible to perform discrotation control during the recording and to generate a recording clock,as well as obtaining information required for the recording of the datapattern, such as a recording address. Incidentally, the pre-formataddress may be recorded in advance by modulating the wobble of thegroove track by a predetermined modulation method, such as frequencymodulation and phase modulation.

Incidentally, in the first example, the optical disc 100 preferablyadopts a ZCLV (Zone Constant Linear Velocity) in which a linear velocityincreases towards the outer side. However, it may adopt another method(e.g. CLV, CAV (Constant Angular Velocity), ZCAV, or the like).

Moreover, as detailed later with reference to FIG. 4 and FIG. 5, thelead-in area 113 of the aforementioned areas may be pre-recorded or maynot be pre-recorded on the optical disc 100 in the first example.

If the lead-in area 113 is pre-recorded, a LRA (Last Recorded Address)which is the address of the end on the outermost side of the datarecording area 114 may be pre-recorded in a CDZ (Control Data Zone) inthe lead-in area 113. In other words, the size of the data recordingarea 114 may be also determined in advance. Moreover, the land pre-pitcan also indicate the LRA. In this case, the LRA pre-recorded in the CDZmatches the LRA indicated by the land pre-pit.

On the other hand, if the lead-in area 113 is not pre-recorded, the sizeof the data recording area 114 may not be determined in advance. In thiscase, after the data pattern is recorded into the data recording area114, the address of the end on the outermost side of an area portion ofthe data recording area 114 in which the data pattern according to thedata to be recorded is recorded is recorded into the CDZ as the LRA.Moreover, the lead-out area 115 is formed to expand to the outer sidefrom the end on the outermost side of the area portion in which the datapattern is recorded of the data recording area 114. On the other hand,even if the lead-in area 113 is not pre-recorded, the land pre-pitindicates the LRA which is the address of the end on the outermost sideof the data recording area 114 which is default in advance. In thiscase, the LRA recorded in the CDZ may not match the LRA indicated by theland pre-pit sometimes.

As described above, the position of the end on the outermost side of thedata recording area 114 can vary depending on whether or not the lead-inarea 113 is pre-recorded. In the first example, the explanation will begiven in the condition that an area portion from the end on theoutermost side of the lead-in area 113 to the position indicated by theLRA indicated by the land pre-pit corresponds to one specific example ofthe “user data area” of the present invention. In other words, theexplanation will be given in the condition that the area portion fromthe end on the outermost side of the lead-in area 113 to the positionindicated by the LRA indicated by the land pre-pit corresponds to thedata recording area 114.

Of course, regardless of whether or not the lead-in area 113 ispre-recorded, it is obvious that effects described later can be obtainedby performing operations described later in the case of the optical disc100 having the aforementioned area structure.

(1-3) Operation Example

Next, with reference to FIG. 3, an explanation will be given on anoperation example of the recording apparatus 1 in the first example(particularly, a recording compensation operation). FIG. 3 is aflowchart conceptually showing a flow of operations of the recordingapparatus 1 in the first example.

Firstly, before the data pattern is recorded into the data recordingarea 114 (or before the recording is performed for the first time at acertain linear velocity), by the operation of the CPU 22, it is judgedwhether or not the currently applied linear velocity is a linearvelocity which allows the data pattern for performing the recordingcompensation operation to be recorded in the inner PCA 111 (step S101).

As a result of the judgment in the step S101, if it is judged that thecurrently applied linear velocity is the linear velocity which allowsthe data pattern for performing the recording compensation operation tobe recorded in the inner PCA 111 (the step S101: Yes), the inner PCA 111is set to an area portion for performing the recording compensationoperation (i.e. a recording compensation area) by the operation of theCPU 22 (step S102). Then, OPC is performed in the inner PCA 111 or theouter PCA 116 (step S103). Then, the data pattern is recorded into therecording compensation area set in the step S102 by using the laser beamwith the optimum power calculated by the OPC in the step S103, therebyperforming the recording compensation operation (step S109).Incidentally, the recording compensation operation will be detailedlater, with reference to FIG. 9.

On the other hand, as a result of the judgment in the step S101, if itis judged that the currently applied linear velocity is not the linearvelocity which allows the data pattern for performing the recordingcompensation operation to be recorded in the inner PCA 111 (the stepS101: No), then, an area portion required to record the data patternwhich is scheduled to be recorded is calculated by the operation of theCPU 22 (step S104). In other words, the size of the data pattern whichis scheduled to be recorded is calculated. That is, the area portion inwhich the data pattern is scheduled to be recorded is identified fromthe data recording area 114.

Then, by the operation of the CPU 22, it is judged whether or not thereis an area portion in which the data pattern is not recorded in the datarecording area 114, on the basis of the calculation result in the stepS104 (step S105).

As a result of the judgment in the step S105, if it is judged that thereis the area portion in which the data pattern is not recorded in thedata recording area 114 (the step S105: Yes), an area portion of thedata recording area 114 in which the data pattern is not scheduled to berecorded is set to the area portion for performing the recordingcompensation operation (step S106). In other words, the area portion ofthe data recording area 114 which is located outer than the end on theouter side of the area portion (i.e. a recording-scheduled area portion)in which the data pattern is scheduled to be recorded and which existsin the data recording area 114 is set to the area portion for performingthe recording compensation operation.

On the other hand, as a result of the judgment in the step S105, if itis judged that there is not the area portion in which the data patternis not recorded in the data recording area 114 (the step S105: No), thearea portion outer than the data recording area 114 is set to the areaportion for performing the recording compensation operation by theoperation of the CPU 22 (step S106).

Here, with reference to FIG. 4 and FIG. 6, the operation of setting thearea portion for performing the recording compensation operation in thestep S106 and the step S107 in FIG. 3 will be explained in more detail.FIG. 4 are area structure diagrams conceptually showing an example ofsetting the area portion for performing the recording compensationoperation targeted at the optical disc 100 in which the lead-in area 113is pre-recorded. FIG. 5 are area structure diagrams conceptually showingan example of setting the area portion for performing the recordingcompensation operation targeted at the optical disc 100 in which thelead-in area 113 is not pre-recorded.

As shown in FIG. 4( a), in the optical disc 100 in which the lead-inarea 113 is pre-recorded, if there is the area portion in which the datapattern according to the data to be recorded is not recorded in the datarecording area 114, the area portion of the data recording area 114 inwhich the data pattern according to the data to be recorded is notscheduled to be recorded is set to the area portion for performing therecording compensation operation. In other words, the area portion (morespecifically, its one portion) which is located outer than the end onthe outer side of the area portion in which the data pattern accordingto the data to be recorded is recorded and which is located inner thanthe area portion indicated by the LRA pre-recorded in the CDZ is set tothe area portion for performing the recording compensation operation.

As shown in FIG. 4( b), in the optical disc 100 in which the lead-inarea 113 is pre-recorded, if there is not the area portion in which thedata pattern according to the data to be recorded is not recorded in thedata recording area 114, the area portion located outer than the datarecording area 114 is set to the area portion for performing therecording compensation operation. In other words, the area portion (morespecifically, its one portion) which is located outer than the areaportion indicated by the LRA pre-recorded in the CDZ is set to the areaportion for performing the recording compensation operation.

As shown in FIG. 5( a), in the optical disc 100 in which the lead-inarea 113 is not pre-recorded, if there is the area portion in which thedata pattern according to the data to be recorded is not recorded in thedata recording area 114, the area portion of the data recording area 114in which the data pattern according to the data to be recorded is notscheduled to be recorded is set to the area portion for performing therecording compensation operation. In other words, the area portion (morespecifically, its one portion) which is located outer than the end onthe outer side of the area portion in which the data pattern accordingto the data to be recorded is recorded and which is located inner thanthe area portion indicated by the LRA indicated by the land pre-pit(i.e. the LRA assigned to the land pre-pit) is set to the area portionfor performing the recording compensation operation. In this case, thearea portion of the data recording area 114 in which the data patternaccording to the data to be recorded is not scheduled to be recorded isoriginally padded by using a padding data pattern with a lead-out areaattribute (e.g. 00h data pattern) or the like, and it is treated as thelead-out area 115 for a reproducing apparatus. In the first example,only the area portion of the data recording area 114 in which the datapattern according to the data to be recorded is not scheduled to berecorded and which is not used for the recording compensation operationis padded by using the padding data pattern with the lead-out areaattribute.

As shown in FIG. 5( b), in the optical disc 100 in which the lead-inarea 118 is not pre-recorded, if there is not the area portion in whichthe data pattern according to the data to be recorded is not recorded inthe data recording area 114, the area portion which is located outerthan the data recording area 114 (more specifically, its one portion) isset to the area portion for performing the recording compensationoperation. In other words, the area portion which is located outer thanthe area portion indicated by the LRA indicated by the land pre-pit isset to the area portion for performing the recording compensationoperation.

Incidentally, in setting the area portion for performing the recordingcompensation operation in the data recording area 114, the recordingcompensation operation is preferably set in view of a positionalrelation with the end on the outer side of the area portion in which thedata pattern according to the data to be recorded is recorded. Such asetting operation will be explained in more detail with reference toFIG. 6. FIG. 6 are area structure diagrams conceptually showing anotherexample of setting the area portion for performing the recordingcompensation operation.

As shown in FIG. 6( a), the area portion for performing the recordingcompensation operation is preferably set to be relatively close to theend on the outer side of the area portion in which the data patternaccording to the data to be recorded is recorded. In other words, thearea portion for performing the recording compensation operation ispreferably set to be closer to the end on the outer side of the areaportion in which the data pattern according to the data to be recordedis recorded, than to the end on the outer side of the data recordingarea 114 pre-recorded in the CDZ or indicated by the LEA indicated bythe land pre-pit.

Alternatively, as shown in FIG. 6( b), the area portion for performingthe recording compensation operation is preferably set to adjacent tothe end on the outer side of the area portion in which the data patternaccording to the data to be recorded is recorded.

However, as shown in FIG. 6( b), the area portion for performing therecording compensation operation is preferably set to be provided withan empty space of a predetermined size (e.g. about IECC block to severalECC blocks) between the area portion for the recording compensationoperation and the end on the outer side of the area portion in which thedata pattern according to the data to be recorded is recorded.

In FIG. 3 again, then, the power of the laser beam LB for performing therecording compensation operation is calculated (step S108).

Now, with reference to FIG. 7, an explanation will be given on theoperation of calculating the power of the laser beam LB for performingthe recording compensation operation. FIG. 7 is a flowchart conceptuallyshowing a flow of the operation of calculating the power of the laserbeam LB for performing the recording compensation operation.

As shown in FIG. 7, firstly, under the control of the CPU 22, an AOPCoperation is performed in the inner PCA 111 (step S301). By this, theoptimum power used in recording the data pattern according to the datato be recorded into the recording-scheduled area portion is calculated.

Incidentally, the AOPC operation is an operation of calculating theoptimum power of the laser beam LB at a linear velocity which cannot berealized in the inner PCA 111 or the outer PCA 116 (e.g. a linearvelocity corresponding to a recording speed of 8×) by the OPC operationin the inner PCA 111 or the outer PCA 116, in consideration of adifference in the properties of the recording surface of the opticaldisc 100 (e.g. a difference in recording sensitivity on the inner side,on the middle side, and on the outer side), a difference in the linearvelocity, or the like. In other words, it is a special OPC operation todissolve such a disadvantage that the OPC is performed in the inner PCA111 in which only a relatively low linear velocity can be realized whilethe linear velocity increases towards the outer side of the optical disc100. According to the AOPC, the recording properties throughout theentire surface of the optical disc 100 can be substantially estimated onthe basis of the result of the OPC performed in the inner PCA 111. Here,considering that the linear velocity increases towards the outer side ofthe optical disc 100, it is possible to substantially estimate therecording properties corresponding to the linear velocity which can berealized on the optical disc 100, by associating the radial position ofthe optical disc 100 with the linear velocity. As a result, it ispossible to estimate the optimum power used in recording the datapattern into an arbitrary area portion of the optical disc 100 (in otherwords, in recording the data pattern at an arbitrary linear velocity).Please refer to International Publication WO2005/043515 pamphlet for thedetails.

However, not only the AOPC but also an operation of calculating theoptimum power of the laser beam LB at the linear velocity which cannotbe realized in the inner PCA 111 or the outer PCA 116 (e.g. the linearvelocity corresponding to a recording speed of 8×) by the OPC operationor other calculations in the inner PCA 111 or the outer PCA 116 can beadopted as the operation in the step S108. For example, the OPC may beperformed in each of the inner PCA 111 and the outer PCA 116, and fromthe results of the OPC performed in the two PCAs, the optimum power usedin recording the data pattern into an area portion located between thetwo PCAs may be calculated by an interpolation process or the like.

Then, under the control of the CPU 22, the data pattern is recorded intothe recording compensation area with the optimum power calculated by theAOPC in the step S201 (step S302). Then, the recorded data pattern isread, and the recording properties (e.g. jitter, asymmetry or the like)are measured.

Then, under the control of the CPU 22, a difference between a recordingsensitivity in the recording-scheduled area portion and a recordingsensitivity in the recording compensation area is calculated (stepS303). Specifically, the result of the AOPC in the step S301 directly orindirectly indicates the recording sensitivity in therecording-scheduled area portion, and the result of the recording of thedata pattern in the step S302 directly or indirectly indicates therecording sensitivity in the recording compensation area. Thus, bycomparing the result in the step S301 with the result in the step S302,it is possible to calculate the difference between the recordingsensitivity in the recording-scheduled area portion and the recordingsensitivity in the recording compensation area. Here, the differencebetween the recording sensitivity in the recording-scheduled areaportion and the recording sensitivity in the recording compensation areamay be directly calculated. Alternatively, considering that thedifference between the recording sensitivity in the recording-scheduledarea portion and the recording sensitivity in the recording compensationarea is indirectly indicated by a difference between recordingproperties in the recording-scheduled area portion and recordingproperties in the recording compensation area, the difference betweenthe recording sensitivity in the recording-scheduled area portion andthe recording sensitivity in the recording compensation area may beindirectly calculated by calculating the difference between therecording properties in the recording-scheduled area portion and therecording properties in the recording compensation area.

Then, under the control of the CPU 22, the power of the laser beam LBfor performing the recording compensation operation used in performingthe recording compensation operation in the recording compensationoperation is calculated on the basis of the difference between therecording sensitivity in the recording-scheduled area portion and therecording sensitivity in the recording compensation area (step S304).

Now, with reference to FIG. 8, a more detailed explanation will be givenon the operation of calculating the power of the laser beam LB used inperforming the recording compensation operation in the recordingcompensation operation (i.e. the power of the laser beam LB forperforming the recording compensation operation). FIG. 8 are graphsconceptually showing the recording properties in the area portion (orthe recording-scheduled area portion) in which the data patternaccording to the data to be recorded is scheduled to be recorded of thedata recording area 114 and the recording properties in the area portion(or the recording compensation area) in which the recording compensationoperation is performed. Incidentally, in FIG. 8, the explanation will begiven in the assumption that a “middle circumference” corresponds to therecording-scheduled area portion, and an “outer circumference”corresponds to the recording compensation area.

FIG. 8( a) shows a graph showing a correlation of jitter vs. power ineach of the middle circumference and the outer circumference of thegeneral optical disc 100. As shown in FIG. 8( a), the middlecircumference and the outer circumference have different optimum powers(in other words, powers with the smallest jitter) due to a differencebetween a recording sensitivity in the middle circumference and arecording sensitivity in the outer circumference. Specifically, theoptimum power in the middle circumference is 30 mW, whereas the optimumpower in the outer circumference is 31.5 mW. Thus, it is considered thatan optimum recording condition (i.e. recording strategy) is notnecessarily obtained even if the recording compensation operation isperformed in the recording compensation area (i.e. the outercircumference in FIG. 8( a)) with the optimum power obtained by the AOPC(i.e. the optimum power in the middle circumference in FIG. 8( a)).

Here, according to a graph in FIG. 8( b) indicating a correlation ofjitter vs. asymmetry in each of the middle circumference and the outercircumference of the general optical disc 100, it is seen that thejitter improved if the asymmetry is uniformed in each of the middlecircumference and the outer circumference (e.g. if it is set toapproximately 0), regardless of whether or not the recording isperformed in the middle circumference or the outer circumference. In thefirst example, the power for compensation is calculated by effectivelyusing such a characteristic. Specifically, the power which realizes thesame asymmetry in the outer circumference (or the recording compensationarea) as the asymmetry with the optimum power in the middlecircumference (or the recording-scheduled area portion) is calculated asa power for performing the recording compensation operation.

Specifically, by reading the data pattern recorded by the operation inthe step S302, as shown in FIG. 8( c), a correlation of power vs.asymmetry in the outer circumference (or the recording compensationarea) is obtained. Now, it is assumed that the optimum power in themiddle circumference (the optimum power obtained by the AOPC) is 30 mWwhich allows an asymmetry of 0. In this case, with the same power, theasymmetry changes to −0.05 in the outer circumference (or the recordingcompensation area). Thus, according to the difference between therecording sensitivity in the inner circumference (or therecording-scheduled area portion) and the recording sensitivity in theouter circumference (or the recording compensation area), 31.4 mW whichis a power which realizes the same asymmetry of 0 in the outercircumference (or the recording compensation area) as the asymmetry withthe optimum power in the middle circumference (or therecording-scheduled area portion) is set as the power for performing therecording compensation operation.

In FIG. 3 again, then, the recording compensation operation is performed(the step S109). More specifically, if it is judged to be Yes in thestep S101, the recording compensation operation is performed in therecording compensation area set in the step S102 by using the laser beamLB with the power calculated by the OPC in the step S103. On the otherhand, if it is judged to be No in the step S101 and if it is judged tobe Yes in the step S105, the recording compensation operation isperformed in the recording compensation area set in the step S106 byusing the laser beam LB with the power calculated in the step S108. Onthe other hand, if it is judged to be No in the step S101 and if it isjudged to be No in the step S105, the recording compensation operationis performed in the recording compensation area set in the step S107 byusing the laser beam LB with the power calculated in the step S108.

After the recording compensation operation, the recording is started atthe set linear velocity, under the control of the CPU 22 (step S110). Inother words, the recording of the data pattern is started by applyingthe laser beam LB with the optimum power calculated in the step S103 orthe step S301 in FIG. 7 and in the optimum recording condition (optimumstrategy) set in the step S109. Then, by the operation of the CPU 22, itis judged whether or not the recording operation is to be ended (stepS111).

As a result of the judgment in the step S111, if it is judged that therecording operation is to be ended (the step S111: Yes), the recordingoperation is ended.

On the other hand, as a result of the judgment in the step S111, if itis judged that the recording operation is not to be ended (the stepS111: No), then, it is judged whether or not the linear velocity is tobe changed by the operation of the CPU 22 (step S112).

As a result of the judgment in the step S112, if it is judged that thelinear velocity is to be changed (the step S112: Yes), the operationalflow returns to the step S101, and the operations after the step S101are repeated.

On the other hand, as a result of the judgment in the step S112, if itis judged that the linear velocity is not to be changed (the step S112:No), the operational flow returns to the step S111, and the recordingoperation is continued.

Next, with reference to FIG. 9, the recording compensation operation inthe step S109 in FIG. 3 will be explained in more detail. FIG. 9 is aflowchart conceptually showing a flow of the recording compensationoperation in the step S109 in FIG. 3.

As shown in FIG. 9, firstly, under the control of the CPU 22, the datapattern is recorded into the area portion, which is set in the stepS102, the step S106, or the step S107 in FIG. 3, for performing therecording compensation operation (step S201). The data pattern recordedhere is the data pattern for performing the recording compensationoperation but not a special data pattern like the OPC pattern, and it isthe same data pattern as a normal data pattern recorded in the datarecording area 114. Then, the jitter is measured by the operation of theaveraging circuit 19 (step S202).

Now, with reference to FIG. 10 and FIG. 11, an explanation will be givenon the operation in measuring the jitter and the averaging circuit 19for measuring the jitter. FIG. 10 is a waveform diagram conceptuallyshowing an operation of measuring the jitter by the averaging circuit19, on the read sample value series RS_(C). FIG. 11 is a block diagramconceptually showing the basic structure of the averaging circuit 19.

As shown in FIG. 10, in the first example, the averaging circuit 19firstly measures a difference (i.e. an edge shift in an amplitudedirection) between a zero level and a sample value (which is shown by ablack circle in FIG. 10 and which will be hereinafter referred to as a“zero cross sample value” as occasion demands) in the vicinity of thezero cross point of the read sample value series RS_(C), for each datapattern, in order to measure the jitter. If there is no intersymbolinterference in the read signal R_(RF), the sample value thatapproximately matches the zero level in the timing of a clock CLKbecomes the zero cross sample value. If there is the intersymbolinterference in the read signal R_(RF), the sample value that is theclosest to the zero level in the timing of the clock CLK is the zerocross sample value.

In order to perform such an operation, the averaging circuit 19 isprovided with a trigger generation device 1911, a total jittermeasurement block 191, n individual shift jitter component measurementblocks 192-1 to 192-n, and a whole shift jitter component measurementcircuit 193, as shown in FIG. 11. The number of the individual shiftjitter component measurement blocks 192-1 to 192-n is equal to thecombination number of types of the data patterns. In other words, if theoptical disc 100 is a DVD, there are 10 types of data run lengths (3T to11T, and 14T). For each mark length, an individual shift jitter can beclassified by using the combination pattern of front and rear spacelengths. For example, there are 100 combinations of the front spacelength and each mark length, and there are 100 combinations of the rearspace length and each mark: n=200 in total. In view of an effectivepupil diameter and the data run length, the same intersymbolinterference occurs in the combination patterns of the marks/spaces of6T or more. Thus, if the data of 6T or more are treated as the samegroup, n can be reduced to n=32. If the optical disc 100 is a Blu-rayDisc, there are 8 types of data run lengths (2T to 9T), so that thecombination patterns of the front and rear space lengths for each marklength is n=8*8*2=128 combinations. As in the DVD, in view of theeffective pupil diameter and the data run length, if the data of 5T ormore are treated as the same group, n can be reduced to n=82. Moreover,each of the individual shift jitter component measurement blocks 192-1to 192-n measures corresponding one of the individual shift jittercomponents in the data patterns.

The read sample value series RS_(C) outputted from the delay circuit 18is inputted to an ABS circuit 1912 and n adders 1923-1 to 1923-n.Moreover, the pattern judgment result outputted from the patternjudgment circuit 20 is inputted to the trigger generation device 1911.

The trigger generation device 1911 generates a trigger signal which isdistinguished in each data pattern and which is at high level (or lowlevel) in timing in which the data pattern is inputted, in accordancewith the pattern judgment result outputted from the pattern judgmentcircuit 20. The trigger signal is inputted to an OR circuit 1917, nsample hold (S/H) circuits 1924-1 to 1924-n, and n counters 1925-1 to1925-n.

Next, the operation of the total jitter measurement block 191 will beexplained. The absolute value of the zero cross sample value outputtedfrom the ABS circuit 1912 is added on an adder 1913. The addition resultis sample-held in timing in which any trigger signal is at high level(or low level) (i.e. in timing in which any data pattern is inputted tothe total jitter measurement block 191), on a sample-holding circuit1914. The result is outputted to a divider 1916 and is fed back to theadder 1913. Thus, a sum of the absolute values of the zero cross samplevalues of all the data patterns is outputted to the divider 1918. On theother hand, a counter 1915 counts the number of times that the triggersignal is at high level (or low level) (i.e. the number of the datapatterns inputted to the total jitter measurement block 191). The countresult is outputted to the divider 1916. The divider 1916 divides thesum of the absolute values of the zero cross sample values by the numberof the data patterns inputted. As a result, an average value of theabsolute values of the zero cross sample values is outputted. In theexample, the average value of the absolute values of the zero crosssample values is a total jitter (i.e. jitter as a whole, which isobtained in consideration of a random jitter component and a shiftjitter component).

Next, the operation of the individual shift jitter component measurementblocks 192-1 to 192-n will be explained. Here, an explanation will begiven on the operation of the individual shift jitter componentmeasurement block 192-1 which corresponds to the zero cross sample valueof the data pattern of a 3T mark in the rear of a space with a runlength of 3T when the optical disc 100 is a DVD. By the actions of theadder 1923-1 and the sample-holding circuit 1924-1, in timing in whichthe trigger signal corresponding to the data pattern of the 3T mark inthe rear of the space with a run length of 3T is at high level (or lowlevel) (i.e. in timing in which a boundary zero cross sample of the 3Tmark in the rear of the 3T space is inputted to the individual shiftjitter component measurement block 192-1), the boundary zero crosssample of the 3T mark in the rear of the 3T space is sample-held. Theresult is outputted to a divider 1926-1 and is fed back to the adder1923-1. In other words, on the adder 1923-1, only the boundary zerocross sample value of the 3T mark in the rear of the 3T space isintegrated, and a sum of the boundary zero cross sample values of the 3Tmark in the rear of the 3T space is outputted to the divider 1926-1. Onthe other hand, a counter 1925-1 counts the number of times N(1) thatthe trigger signal is at high level (or low level) (i.e. the number ofthe boundary zero cross samples of the 3T mark in the rear of the 3Tspace inputted to the individual shift jitter component measurementblock 192-1). The count result is outputted to the divider 1926-1. Thedivider 1926-1 divides the sum of the boundary zero cross sample valuesof the 3T mark in the rear of the 3T space by the inputted N(1). As aresult, an average value S(1) of the boundary zero cross sample valuesof the 3T mark in the rear of the 3T space is outputted. This operationis performed for each corresponding data pattern, on the otherindividual shift jitter component measurement blocks 192-2 to 192-n. Inthe example, the average values of the zero cross sample values in therespective data patterns are individual shift jitter components S(1) toS(n).

The individual shift jitter components S(1) to S(n) in the respectivedata patterns are also outputted to the whole shift jitter componentmeasurement circuit 193. Moreover, the number of times N(1) to N(n) thatthe trigger signal is at high level are also outputted to the wholeshift jitter component measurement circuit 193. On the whole shiftjitter component measurement circuit 193, a shift jitter component as awhole obtained in consideration of the occurrence probability of theindividual shift jitter components in the respective data patterns isoutputted by performing an arithmetic operation shown in an Equation 1.

$\begin{matrix}\sqrt{\sum\limits_{i = 1}^{n}\; {{S(i)}^{2}\frac{N(i)}{\sum\limits_{j = 1}^{n}\; {N(j)}}}} & \left\lbrack {{Equation}\mspace{14mu} 1} \right\rbrack\end{matrix}$

In FIG. 9 again, then, under the control of the CPU 22, it is judgedwhether or not the individual shift jitter components of the jittermeasured in the step S202 are less than a first threshold value (stepS203). The judgment is performed in each data pattern. In other words,the judgment is performed on each of the individual shift jittercomponents measured on the individual shift jitter component measurementblocks 192-1 to 192-n. Specifically, if the optical disc 100 is a DVDand 6T or more are treated as the same group, the judgment in the datapattern of a front space with a run length of 3T, the judgment in thedata pattern of a front space with a run length of 4T, the judgment inthe data pattern of a front space with a run length of 5T, and thejudgment in the data pattern of a front space of a run length of 6T areperformed with respect to the 3T mark. In the same manner, the judgmentsin the data patterns of the front spaces with run lengths of 3T, 4T, 5T,and 6T or more are performed with respect to marks with 4T or more. Thejudgments in the data patterns of rear spaces with run lengths of 3T,4T, 5T, and 6T or more are performed with respect to marks with 3T, 4T,5T, and 6T or more. Although 6T or more are treated as the unifiedgroup, if the recording compensation is performed with respect to aninfluence of coma aberration or the like by a tangential tilt, it ispossible to treat the influenced data pattern, or individually treat 3Tto 11T and 14T. On the other hand, if the optical disc 100 is a Blu-rayDisc and 5T or more are treated as the same group, the judgment in thedata patterns of front spaces or rear spaces with 2T, 3T, 4T, and 5T ormore is performed with respect to marks with 2T, 3T, 4T, and 5T or more.Although 5T or more are treated as the unified group, as in the DVD, ifthe recording compensation is performed with respect to the influence ofcoma aberration or the like by the tangential tilt, it is possible totreat the influenced data pattern, or individually treat 2T to 9T.

Incidentally, a value common to all the data patterns may be used as thefirst threshold value or an individual value for each data pattern (oreach group including a plurality of data patterns) may be used as thefirst threshold value. Moreover, the specific value of the firstthreshold value is preferably set to realize that a ratio of the randomjitter component to the jitter is greater than or equal to apredetermined value (e.g. approximately 80% as described later).Incidentally, the recording compensation operation may be performed suchthat the ratio of the random jitter component to the total jitter isgreater than or equal to approximately 80%. However, in order to furtherreduce the total jitter, the recording compensation operation may beperformed such that the ratio of the random jitter component to thetotal jitter is greater than or equal to approximately 90%.

As a result of the judgment in the step S203, if it is judged that theshift jitter components in at least one or all of the data patterns areless than the first threshold value (the step S203: Yes), the operationis ended.

On the other hand, as a result of the judgment in the step S203, if itis judged that the shift jitter components in at least one or all of thedata patterns are not less than the first threshold value (the stepS203: No), the operation of adjusting the strategy, which is therecording compensation operation, is performed (step S204).

Here, the recording compensation may be performed on the data patterncorresponding to the shift jitter component that is judged not to beless than the first threshold value. Alternatively, in addition to thedata pattern corresponding to the shift jitter component that is judgednot to be less than the first threshold value, the recordingcompensation may be performed on the data pattern corresponding to theshift jitter component that is judged to be less than the firstthreshold value.

Here, with reference to FIG. 12, the recording compensation operation inthe step S204 in FIG. 9 will be explained. FIG. 12 is a graphconceptually showing the states of the shift jitter components in therespective data patterns and the shift jitter component as a wholebefore recording compensation and the states of the shift jittercomponents in the respective data patterns and the shift jittercomponent as a whole after the recording compensation. The average valueof a distribution in each data pattern is the individual shift jittercomponent.

As shown in FIG. 12, in the first example, such a recording compensationoperation is performed that the variations of each of the individualshift jitter components in the respective data patterns is reduced oreliminated. More specifically, if the jitter distributions in therespective data patterns have variations on the basis of the risingpoint of the clock shown by a longitudinal arrow as shown on the leftside of FIG. 12, the recording compensation operation is performed suchthat the jitter distributions in the respective data patterns areshifted to the rising point of the clock as shown on the right side ofFIG. 12. In other words, the recording compensation operation isperformed such that the jitter distributions in the respective datapatterns match at or in the vicinity or the rising point of the clock.In other words, the recording compensation operation is performed suchthat the jitter distributions in the respective data patterns are equal.As a result, the jitter distribution as a whole (i.e. total jitterdistribution) is a normal distribution centered on the rising positionof the clock or the like. Namely, in the recording compensationoperation in the example, instead of reducing the widths of the jitterdistributions in the respective data patterns (in other words, insteadof reducing the random jitter component), the average values of thejitter distributions in the respective data patterns are matched. Thiscorresponds to an operation of reducing the individual shift jittercomponents in the respective data patterns.

In order to reduce the individual shift jitter components in therespective data patterns, the recording strategy adjustment circuit 21adjusts the recording strategy, for example, as shown in FIG. 13 to FIG.15. FIG. 13 is a timing chart conceptually showing a first aspect of therecording strategy adjustment operation. FIG. 14 is a timing chartconceptually showing a second aspect of the recording strategyadjustment operation. FIG. 15 is a timing chart conceptually showing athird aspect of the recording strategy adjustment operation.

For example, as shown in FIG. 13, the pulse width of a recording pulse(i.e. recording strategy) which defines the waveform of the laser beamfor recording the data pattern (record data) may be adjusted.

Moreover, as shown in FIG. 14, the amplitudes (e.g. a top pulseamplitude Po, a middle pulse amplitude Pm, a bias power amplitude Pb) ofthe recording pulse (i.e. recording strategy) which define the waveformof the laser beam for recording the data pattern (record data) may beadjusted. Here, as shown in the recording pulse on the top in FIG. 14,the amplitudes of the recording pulse corresponding to the data patternswith run lengths of 3T and 4T and the amplitudes of the recording pulsecorresponding to the data patterns with run lengths of 5T or more may beseparately adjusted. Alternatively, as shown in the second recordingpulse from the top in FIG. 14, the amplitudes of the recording pulsecorresponding to the data pattern with a run length of 3T, theamplitudes of the recording pulse corresponding to the data pattern witha run length of 4T, the amplitudes of the recording pulse correspondingto the data pattern with a run length of 5T, and the amplitudes of therecording pulse corresponding to the data pattern with run lengths of 6Tor more may be separately adjusted. Alternatively, as shown in the thirdrecording pulse from the top in FIG. 14, the amplitudes of the recordingpulse corresponding to the data pattern with a run length of 3T, theamplitudes of the recording pulse corresponding to the data pattern witha run length of 4T, and the amplitudes of the recording pulsecorresponding to the data pattern with run lengths of 5T or more may beseparately adjusted. Alternatively, as shown in the fourth recordingpulse from the top in FIG. 14, the amplitudes of the recording pulsecorresponding to the data pattern with a run length of 3T and theamplitudes of the recording pulse corresponding to the data pattern withrun lengths of 4T or more may be separately adjusted.

Moreover, as shown in FIG. 15, even if the recording pulse is not of acastle type, as in the case shown in FIG. 14, the amplitudes of therecording pulse (i.e. the recording strategy) which define the waveformof the laser beam for recording the data pattern (or record data) may beadjusted.

Of course, it is obvious that the recording strategy may be adjusted bycombining the adjustment of the pulse width of the recording pulse asshown in FIG. 13 and the adjustment of the amplitudes of the recordingpulse as shown in FIG. 14 and FIG. 15, as occasion demands.

As explained above, according to the recording apparatus 1 in theexample, it is possible to reduce the total jitter by performing therecording compensation operation. Now, with reference to FIG. 16, thereduction effect of the total jitter will be explained. FIG. 16 is agraph conceptually showing total jitter of the data patterns recordedwithout performing the recording compensation operation and total jitterof the data pattern recorded after the recording compensation operationis performed in an aspect associated with the first example.

As shown in the upper part of FIG. 16, the total jitter varies widely onthe recording apparatus which does not perform the recordingcompensation operation. On the other hand, on the recording apparatuswhich performs the recording compensation operation, the total jitter isreduced, and there axe small variations or little variation in the totaljitter in comparison with the recording apparatus which does not performthe recording compensation operation.

In particular, in the first example, before the recording compensationoperation is performed (in other words, the data pattern for adjustingthe recording condition is recorded), the power for performing therecording compensation operation is calculated in consideration of thedifference between the recording sensitivity in the recording-scheduledarea portion and the recording sensitivity in the recording compensationoperation area.

Now, with reference to FIG. 17 and FIG. 18, an explanation will be givenon the recording property if the recording compensation operation isperformed after calculating the power for performing the recordingcompensation operation in consideration of the difference in recordingsensitivity and the recording property if the recording compensationoperation is performed after calculating the optimum power calculated bythe OPC without consideration of the difference in recordingsensitivity. FIG. 17 is a graph conceptually showing the recordingproperty in the case where the recording compensation operation isperformed after calculating the optimum power calculated by the OPCwithout consideration of the difference in recording sensitivity. FIG.18 is a graph conceptually showing the recording property in the casewhere the recording compensation operation is performed aftercalculating the power for performing the recording compensationoperation in consideration of the difference in recording sensitivity.

In the graph in FIG. 17, the graph indicated by “without recordingcompensation” indicates the recording property in the case where thedata pattern is recorded into the middle circumference (or therecording-scheduled area portion) without performing the recordingcompensation. The graph indicated by “with recording compensation”indicates the recording property in the case where the data pattern isrecorded into the middle circumference (or the recording-scheduled areaportion) after performing the recording compensation in the middlecircumference (or the recording-scheduled area portion). The graphindicated by “with recording compensation (outer circumference)”indicates the recording property in the case where the data pattern isrecorded into the middle circumference (or the recording-scheduled areaportion) after performing the recording compensation in the outercircumference (or the recording compensation area) without considerationof the difference in recording sensitivity. As shown in FIG. 17, if thedata pattern is recorded into the middle circumference (or therecording-scheduled area portion) after performing the recordingcompensation in the outer circumference (or the recording compensationarea) without consideration of the difference in recording sensitivity,the recording property (or jitter) obtained with the optimum power (i.e.a power of 30 mW) deteriorates in the middle circumference (or therecording-scheduled area portion).

In the graph in FIG. 18, the graph indicated by “without recordingcompensation” indicates the recording property in the case where thedata pattern is recorded into the middle circumference (or therecording-scheduled area portion) without performing the recordingcompensation. The graph indicated by “with recording compensation”indicates the recording property in the case where the data pattern isrecorded into the middle circumference (or the recording-scheduled areaportion) after performing the recording compensation in the middlecircumference (or the recording-scheduled area portion). The graphindicated by “with recording compensation (outer circumference)”indicates the recording property in the case where the data pattern isrecorded into the middle circumference (or the recording-scheduled areaportion) after performing the recording compensation in the outercircumference (or the recording compensation area) in consideration ofthe difference in recording sensitivity. As shown in FIG. 18, if thedata pattern is recorded into the middle circumference (or therecording-scheduled area portion) after performing the recordingcompensation in the outer circumference (or the recording compensationarea) in consideration of the difference in recording sensitivity, itcan be seen that the recording property (or jitter) obtained with theoptimum power (i.e. a power of 30 mW) does not deteriorate in the middlecircumference (or the recording-scheduled area portion).

In summary, if the recording compensation operation is performed in therecording compensation area which is outer than the recording-scheduledarea portion by using the optimum power which is optimal in therecording-scheduled area portion without consideration of the differencein recording sensitivity, the optimum power in the recording-scheduledarea portion is not necessarily optimal even in the recordingcompensation area. Thus, the recording compensation operation is likelyperformed with the power which is not optimal in the recordingcompensation operation. This is not preferable from the viewpoint ofpreferable adjustment of the recording condition. In the first example,however, the power of the laser beam LB for performing the recordingcompensation operation is calculated in consideration of the differencein recording sensitivity, so that the recording compensation operationis performed with the optimum power in the recording compensation area.On the other hand, when the data pattern is actually recorded into therecording-scheduled area portion, the optimum power in therecording-scheduled area is used, so that the data pattern can bepreferably recorded in the recording-scheduled area portion. In otherwords, the data pattern can be recorded without deteriorating therecording quality of the data pattern.

In addition, the recording compensation operation can be performed in anarea portion closer to the area portion in the data recording area 114in which the data pattern is actually recorded in comparison with theinnermost PCA 111 or the outermost PCA 116. Thus, the properties of thearea portion in which the recording compensation operation is performedare no longer far removed from the properties of the area portion inwhich the data pattern is actually recorded. This increases thepossibility that the strategy optimized by the recording compensationoperation is preferable or optimal in the data recording area 114 inwhich the data pattern is actually recorded, in comparison with a casewhere the recording compensation operation is performed in the innermostPCA 111 or the outermost PCA 116. In other words, by performing therecording compensation operation in a more preferable aspect, it ispossible to optimize the strategy, more preferably. Therefore, the datapattern can be recorded into the data recording area 114, morepreferably, by using the strategy optimized by the recordingcompensation operation.

Now, an influence of a change in the properties on the recording surfaceof the optical disc 100 with respect to the jitter or the like will beexplained with reference to FIG. 19 to FIG. 21. FIG. 19 a graph in whichthe jitter and asymmetry are associated with the radial position of theoptical disc 100. FIG. 20 are graphs conceptually showing a relationbetween the presence of a sensitivity change and the jitter and theasymmetry. FIG. 21 are waveform diagrams conceptually showing the totaljitter and asymmetry of the data pattern recorded by the recordingapparatus which does not perform the recording compensation operationand the total jitter and asymmetry of the data pattern recorded by therecording apparatus 1 which has performed the recording compensationoperation in the outer PCA 116, in association with the radial positionof the optical disc 100.

As shown in FIG. 19, near the outer PCA 116 of the optical disc 100, therecording properties vary widely in comparison with the other areaportion. This is considered to be due to the change in recordingsensitivity caused by a change in thickness of a recording film.

Now, the recording sensitivity in the area portion on the optical discis expressed by percentage (%) on the basis of the sensitivity in themiddle portion of the optical disc 100 (in other words, near the centerof the data recording area 114). Here, FIG. 20( a) is a graph showing achange in the jitter and asymmetry when the data pattern is recordedinto or near a certain area portion (in other words, the area portion inwhich the recording compensation operation is performed) after therecording compensation operation is performed in the same area portion.An area portion with a sensitivity change amount of 0% corresponds tothe middle portion of the optical disc 100, and an area portion with asensitivity change amount of −10% substantially corresponds to the outerPCA 116. In other words, the sensitivity change amount on the horizontalaxis in FIG. 20( a) indicates the change amount of the recordingsensitivity in the area portion in which the recording compensationoperation is performed (or the recording sensitivity in the area portionin which the data pattern is actually recorded) if the middle portion ofthe optical disc 100 is used as the base. As shown in FIG. 20( a), evenif there is a sensitivity change on the recording surface of the opticaldisc 100, the jitter does not vary widely when the data pattern isrecorded into the area portion which is the same as or close to the areaportion in which the recording compensation operation is performed.Specifically, even if the recording compensation operation is performedin the area portion with a sensitivity change amount of −10%corresponding to the outer PCA 116, as long as the data pattern isrecorded into the outer PCA 116 by using the strategy adjusted there,the jitter is kept approximately 6.5%.

However, when the data pattern is recorded into the area portion whichis different from or away from the area portion in which the recordingcompensation operation is performed, the jitter likely varies widely.FIG. 20( b) is a graph showing a change in the jitter and asymmetry whenthe data pattern is recorded into the middle portion of the optical disc100 with a sensitivity change amount of 0% after the recordingcompensation operation is performed in the condition that there is achange in recording sensitivity, after the recording compensationoperation is performed in a certain area portion. In other words, thesensitivity change amount on the horizontal axis in FIG. 20( b)indicates the change amount of the recording sensitivity in the areaportion in which the recording compensation operation is performed ifthe recording sensitivity in the area portion in which the data patternis actually recorded is used as the base. As shown in FIG. 20( b), ifthe recording compensation operation is performed in the outer PCA 116because the recording compensation operation cannot be performed in theinner PCA 111, preferable recording cannot be performed in most areaportions of the data recording area 114 whose recording sensitivity isabout 10% different from that of the outer PCA 116. Specifically, if thedata pattern is recorded into the data recording area 114 correspondingto the area portion with a sensitivity change amount of 0% by using thestrategy adjusted in the outer PCA 116 after the recording compensationoperation is performed in the outer PCA 116, the jitter deterioratesabove approximately 11%.

As described above, the fact that the jitter deteriorates if the datapattern is recorded into the data recording area 114 corresponding tothe area portion with a sensitivity change amount of −10% by using thestrategy adjusted in the outer PCA 116 after the recording compensationoperation is performed in the outer PCA 116 is also clear from thegraphs shown in FIG. 21.

In the example, however, if the recording compensation operation cannotbe performed in the inner PCA 111, the recording compensation operationis performed in the data recording area 114. Therefore, in comparisonwith the case where the recording compensation operation is performed inthe innermost PCA 111 or the outermost PCA 116, the strategy optimizedby the recording compensation operation is highly likely preferable oroptimal even in the data recording area 114 in which the data pattern isactually recorded. Thus, even if there is the sensitivity change on therecording surface of the optical disc 100, it is possible to preferablyadjust the strategy and to ensure the preferable recording operation.

Incidentally, in the first example, the power for performing therecording compensation operation is calculated in consideration of theaforementioned recording sensitivity. Thus, even if therecording-scheduled area portion and the recording compensation area arelocated away from each other, it is not considered to be particularlyproblematic. However, considering the fact that it is more preferablethat the properties in the recording-scheduled area portion are closerto the properties in the recording compensation area, therecording-scheduled area portion is preferably closer to the recordingcompensation area. In this regard, in the first example, it is possibleto receive such a great effect that the recording compensation operationcan be performed, more preferably.

Moreover, in the aforementioned background art, the special data patternfor OPC is recorded into the area portion of the data recording area 114in which the data pattern is not scheduled to be recorded. Thus,considering that bringing the area portion in which the special datapattern is recorded close to the area portion in which the data patternis recorded may cause a runaway operation if a reproducing apparatusmistakenly reads the special data pattern, it is not preferable. On theother hand, according to the first example, in order to perform therecording compensation operation, the normal data pattern is recordedinto the area portion of the data recording area 114 in which the datapattern according to the data to be recorded is not scheduled to berecorded. Thus, even if the reproducing apparatus reads the data patternby bringing the area portion in which the normal data pattern isrecorded close to the area portion in which the data pattern accordingto the data to be recorded is recorded, that does not cause the runwayoperation. Even in this regard, according to the first example, it ispossible to receive excellent effects in comparison with the backgroundart.

(2) Second Example

Next, with reference to FIG. 22, a second example of the recordingapparatus of the present invention will be explained. FIG. 22 is a blockdiagram conceptually showing the basic structure of a recordingapparatus 2 in the second example. Incidentally, the same constituentsas those of the aforementioned information recording apparatus 1 in thefirst example will carry the same referential numerals, and theexplanation thereof will be omitted.

As shown in FIG. 22, the recording apparatus 2 in the second example isprovided with a spindle motor 10, a pickup 11, a HPF 12, an A/Dconverter 13, a pre-equalizer 14, a binary circuit 16, a decodingcircuit 17, a delay circuit 18, an averaging circuit 19, a patternjudgment circuit 20, a recording strategy adjustment circuit 21, and aCPU 22, as in the recording apparatus 1 in the first example.

The recording apparatus 2 in the second example is provided particularlywith a limit equalizer 15 between the pre-equalizer 14 and each of thedelay circuit 18 and the binary circuit 16. The limit equalizer 15constitutes one specific example of the “amplitude limit filteringdevice” of the present invention. The limit equalizer 15 performs ahigh-frequency emphasis process on the read sample value series RS_(C)without increasing the intersymbol interference, and it outputs aresulting high-frequency emphasized read sample value series RS_(H) toeach of the binary circuit 16 and the delay circuit 18. Incidentally,the operations of the limit equalizer 15 are the same as those of aconventional limit equalizer. Please refer to Japanese Patentpublication No. 3459563 for the details.

As a result, the binary circuit 16, the decoding circuit 17, the delaycircuit 18, the averaging circuit 19, the pattern judgment circuit 20,the recording strategy adjustment circuit 21, and the CPU 22 locatedafter the limit equalizer 15 use the high-frequency emphasized readsample value series RS_(H) to perform the operations, instead of theread sample value series RS_(C).

As described above, according to the second example, the patternjudgment is performed as well as performing the recording compensationoperation, by using the output of the limit equalizer 15 (i.e. thehigh-frequency emphasized read sample value series RS_(H)). In otherwords, the pattern judgment is performed as well as performing therecording compensation operation, with the amplitude level of theshortest data pattern emphasized. In any states of the asymmetry of theread signal, it is possible to preferably prevent such a state that theshortest data pattern included in the read signal does not cross thezero level. As a result, the shortest data pattern can be preferablydetected. This preferably allows the recording compensation operation tobe performed with reference to the read signal including the shortestdata pattern. In other words, regardless of the state of the asymmetryin the read signal before the recording compensation, the recordingcompensation operation can be preferably performed.

(3) Third Example

Next, with reference to FIG. 23, a third example of the recordingapparatus of the present invention will be explained. FIG. 23 is a blockdiagram conceptually showing the basic structure of a recordingapparatus 3 in the third example. Incidentally, the same constituents asthose of the aforementioned recording apparatus 1 in the first exampleand the recording apparatus 2 in the second example will carry the samereferential numerals, and the explanation thereof will be omitted.

As shown in FIG. 23, the recording apparatus 3 in the third example isprovided with a spindle motor 10, a pickup 11, a HPF 12, an A/Dconverter 13, a pre-equalizer 14, a limit equalizer 15, a binary circuit16, a decoding circuit 17, a delay circuit 18, an averaging circuit 19,a pattern judgment circuit 20, a recording strategy adjustment circuit21, and a CPU 22, as in the recording apparatus 2 in the second example.

The recording apparatus 3 in the third example is provided particularlywith an adder 23 and a reference level detection circuit 24, each ofwhich constitutes one specific example of the “adding device” of thepresent invention.

The reference level detection circuit 24 outputs a difference betweenthe asymmetry which is actually detected and the asymmetry which istargeted, as offset OFS to the adder 23. On the adder 23, the OFSoutputted recording compensation operation can be preferably performed.

(3) Third Example

Next, with reference to FIG. 23, a third example of the recordingapparatus of the present invention will be explained. FIG. 23 is a blockdiagram conceptually showing the basic structure of a recordingapparatus 3 in the third example. Incidentally, the same constituents asthose of the aforementioned recording apparatus 1 in the first exampleand the recording apparatus 2 in the second example will carry the samereferential numerals, and the explanation thereof will be omitted.

As shown in FIG. 23, the recording apparatus 3 in the third example isprovided with a spindle motor 10, a pickup 11, a HPF 12, an A/Dconverter 13, a pre-equalizer 14, a limit equalizer 15, a binary circuit16, a decoding circuit 17, a delay circuit 18, an averaging circuit 19,a pattern judgment circuit 20, a recording strategy adjustment circuit21, and a CPU 22, as in the recording apparatus 2 in the second example.

The recording apparatus 3 in the third example is provided particularlywith an adder 23 and a reference level detection circuit 24, each ofwhich constitutes one specific example of the “adding device” of thepresent invention.

The reference level detection circuit 24 outputs a difference betweenthe asymmetry which is actually detected and the asymmetry which istargeted, as offset OFS to the adder 23. On the adder 23, the OFSoutputted from the reference level detection circuit 24 is added to thehigh-frequency emphasized read sample value series RS_(H) outputted fromthe limit equalizer 15. This allows the reference level of thehigh-frequency emphasized read sample value series RS_(H) to be set to apredetermined value.

Incidentally, a signal detected from the read signal on the referencelevel detection circuit 24 is not limited to the aforementionedasymmetry but may be a β value. Alternatively, it may be a partial βvalue indicating the deviation between the amplitude center of the readsignal corresponding to the record data with the shortest run length andthe amplitude center of the read signal corresponding to the record datawith the second shortest run length. Alternatively, it may be an α valueindicating a deviation ratio (or rate) of the amplitude center of theread signal corresponding to the record data with the shortest runlength, with respect to the amplitude center (i.e. the reference level,and the zero level in the example) of the read signals corresponding tothe respective record data with all types of run lengths (e.g. therecord data with each of run lengths of 3T to 11T and 14T if the opticaldisc 100 is a DVD, and the record data with each of run lengths of 2T to9T if the optical disc 100 is a Blu-ray Disc).

By adopting such a structure, the recording apparatus 3 in the thirdexample can change the reference level, thereby arbitrarily setting theasymmetry of the read signal after the recording compensation.Therefore, it is possible to perform the recording compensationoperation which realizes an optimum jitter value and the desiredasymmetry. For example, if the optical disc 100 is a DVD, it is possibleto perform the recording compensation operation which realizes theminimum jitter value and the asymmetry of +5%. In the same manner, ifthe optical disc 100 is a Blu-ray Disc, it is possible to perform therecording compensation operation which realizes the minimum jitter valueand the asymmetry of +2.5%.

Moreover, since the asymmetry of the read signal after the recordingcompensation can be set to a desired value without depending on theasymmetry of the read signal before the recording compensation, it ispossible to perform the good recording compensation operation even ifthe asymmetry varies depending on the individual difference of theoptical disc 100 and the recording apparatus 3.

Moreover, since such construction that the offset corresponding to thedifference between the detected asymmetry and the target asymmetry (i.e.such construction that the desired asymmetry is obtained after therecording compensation by adding the offset to the asymmetry before therecording compensation) is adopted, it is possible to set the asymmetryto the desired value even if the asymmetry before the recordingcompensation varies due to the recording compensation operation which isperformed a plurality of times.

Moreover, since it is unnecessary to adjust the asymmetry by adjustingthe recording power (i.e. the amplitude of the recording pulse), it ispossible to simplify an operation of adjusting a recording condition,and it is also possible to reduce a time required for the operation ofadjusting the recording condition.

Incidentally, in the third example, the recording compensation operationis performed by using the high-frequency emphasized read sample valueseries RS_(H) outputted from the limit equalizer 15. However, from theviewpoint that the asymmetry of the read signal after the recordingcompensation can be set to the desired value, the recording compensationoperation is not necessarily performed by using the high-frequencyemphasized read sample value series RS_(H) outputted from the limitequalizer 15. In other words, even if the recording compensationoperation is performed by using the read sample value series RS_(C)outputted from the pre-equalizer 14, obviously, it is possible toreceive the effect that the asymmetry of the read signal after therecording compensation can be set to the desired value. Therefore, inthe third example, the limit equalizer 15 is not necessarily provided.

Incidentally, the result of the recording compensation operation may berecorded onto the optical disc 100 at each time of the recordingoperation, as occasion demands. Namely, it may be recorded onto theoptical disc 100 when the recording operation is performed by a user, asoccasion demands. Alternatively, it may be recorded on the optical disc100 in advance by using embossed pits, prewriting, or the like, in themanufacturing of the optical disc 100. In this case, it may be recordedin the RMA 112 shown in FIG. 2, a CDZ (Control Data Zone) in the lead-inarea 113, or another area portion. In any cases, the aforementionedeffects can be preferably received. In this case, information indicatingthe result of the recording compensation operation is preferablyrecorded in association with identification information which canidentify the recording apparatus 1 (or 2 or 3) which has performed therecording compensation operation.

As described above, by recording the information indicating the resultof the recording compensation operation and the identificationinformation which can identify the recording apparatus 1 that hasperformed the recording compensation operation onto the optical disc100, it is possible to read the result of the recording compensationoperation corresponding to the identification information about therecording apparatus 1, from the optical disc 100, when the data patternis recorded by the recording apparatus 1. Thus, if the read result ofthe recording compensation operation is used to set the aforementionedrecording condition, it is possible to receive the same various effectsas those described above, in the recording operation performed on theoptical disc 100 without the recording compensation operation.

Moreover, even if the result of the recording compensation operationcorresponding to the identification information about the recordingapparatus 1 is not recorded on the optical disc 100, the same effectscan be appropriately received by reading a result of the recordingcompensation operation corresponding to identification information closeto the identification information about the recording apparatus 1 (inother words, identification information about another recordingapparatus which has a similar property to that of the recordingapparatus 1) and by using the read result of the recording compensationoperation to set the aforementioned recording condition. Alternatively,the same effects can be also appropriately received by performing thesimple recording compensation operation on the basis of the result ofthe recording compensation operation corresponding to the identificationinformation close to the identification information about the recordingapparatus 1.

Moreover, even if the information indicating the result of the recordingcompensation operation is not recorded on the optical disc 100 for thereason that that the optical disc 100 is blank or the like, therecording compensation operation can be preferably performed by usingeach of the recording apparatuses in the aforementioned examples.Moreover, if the resulting recording condition is recorded on theoptical disc 100 in association with the identification informationabout the recording apparatus 1, it is possible to receive the samevarious effects as those described above, in the recording performed onthe optical disc 100, without performing the recording compensationoperation again.

In other words, without performing the recording compensation operationor with the recording compensation operation performed at least once, itis possible to receive the same various effects as those describedabove, in the recording performed on the optical disc 100, withoutperforming the recording compensation operation on the correspondingrecording apparatus 1. Therefore, it is possible to reduce the number oftimes that the recording compensation operation is performed, therebysaving an area required for the recording compensation operation.

The present invention is not limited to the aforementioned examples, butvarious changes may be made, if desired, without departing from theessence or spirit of the invention which can be read from the claims andthe entire specification. A recording apparatus and method, a computerprogram, and a recording medium, all of which involve such changes, arealso intended to be within the technical scope of the present invention.

1-14. (canceled)
 15. A recording apparatus comprising: a recordingdevice for recording a desired data pattern onto a recording mediumcomprising an inner area and a user data area located on an outer sideof the inner area; a first calculating device for calculating an optimumpower, which is used in recording the data pattern into arecording-scheduled area portion, before the data pattern is recordedinto the recording-scheduled area portion which is an area portion inthe user data area in which the data pattern is scheduled to be recordedby the recording device; a first controlling device for controlling therecording device to record the data pattern with the optimum power intoan area portion which is outer than an end on an outer side of therecording-scheduled area portion; a second calculating device forcalculating an adjustment power, which is used in adjusting a recordingcondition of the recording device in an area portion which is outer thanthe end on the outer side of the recording-scheduled area portion, inconsideration of a difference between a recording sensitivity in therecording-scheduled area portion and a recording sensitivity in the areaportion which is outer than the end on the outer side of therecording-scheduled area portion, by reading the data pattern recordedby the control of the first controlling device; a second controllingdevice for controlling the recording device to record the data patternfor adjusting the recording condition with the adjustment power into thearea portion which is outer than the end on the outer side of therecording-scheduled area portion; a reading device for reading the datapattern recorded by the control of the second controlling device,thereby obtaining a read signal; a measuring device for measuring jitterof the read signal; an adjusting device for adjusting the recordingcondition such that the jitter measured by the measuring devicesatisfies a desired condition; and a third controlling device forcontrolling the recording device to start the recording of the datapattern into the recording-scheduled area portion by using the optimumpower and the recording condition adjusted by the adjusting device. 16.The recording apparatus according to claim 15, wherein the secondcalculating device calculates the adjustment power which allows optimumrecording properties of the data pattern recorded by the control of thefirst controlling device.
 17. The recording apparatus according to claim15, wherein the second calculating device calculates the adjustmentpower which absorbs the difference between the recording sensitivity inthe recording-scheduled area portion and the recording sensitivity inthe area portion which is outer than the end on the outer side of therecording-scheduled area portion.
 18. The recording apparatus accordingto claim 15, wherein the first calculating device calculates the optimumpower, which is used in recording the data pattern at a first linearvelocity into the recording-scheduled area portion, by controlling therecording device to record the data pattern for test writing at a secondlinear velocity, which is lower than the first linear velocity, in theinner area before the data pattern is recorded at the first linearvelocity into the recording-scheduled area portion, the firstcontrolling device controls the recording device to record the datapattern with the optimum power and at the first linear velocity into thearea portion which is outer than the end on the outer side of therecording-scheduled area portion, the second calculating devicecalculates the adjustment power, which is used in adjusting therecording condition of the recording device at the first linear velocityin the area portion which is outer than the end on the outer side of therecording-scheduled area portion, in consideration of the differencebetween the recording sensitivity in the recording-scheduled areaportion and the recording sensitivity in the area portion which is outerthan the end on the outer side of the recording-scheduled area portion,by reading the data pattern recorded by the control of the firstcontrolling device, the second controlling device controls the recordingdevice to record the data pattern for adjusting the recording conditionwith the adjustment power and at the first linear velocity into the areaportion which is outer than the end on the outer side of therecording-scheduled area portion, and the third controlling devicecontrols the recording device to start the recording of the data patterninto the recording-scheduled area portion at the first linear velocityby using the optimum power and the recording condition adjusted by theadjusting device.
 19. The recording apparatus according to claim 18,wherein the first calculating device calculates the optimum power if thedata pattern for adjusting the recording condition at the first linearvelocity cannot be recorded into the inner area, the first controllingdevice controls the recording device to record the data pattern with theoptimum power and at the first linear velocity into the area portionwhich is outer than the end on the outer side of the recording-scheduledarea portion if the data pattern for adjusting the recording conditionat the first linear velocity cannot be recorded into the inner area, thesecond calculating device calculates the adjustment power if the datapattern for adjusting the recording condition at the first linearvelocity cannot be recorded into the inner area, and the secondcontrolling device controls the recording device to record the datapattern for adjusting the recording condition with the adjustment powerand at the first linear velocity into the area portion which is outerthan the end on the outer side of the recording-scheduled area portionif the data pattern for adjusting the recording condition at the firstlinear velocity cannot be recorded into the inner area.
 20. Therecording apparatus according to claim 15, further comprising: anamplitude limit filtering device for limiting an amplitude level of theread signal by using a predetermined amplitude limit value, therebyobtaining an amplitude limit signal and for performing a high-frequencyemphasis filtering process on the amplitude limit signal, therebyobtaining an equalization-corrected signal; and a detecting device fordetecting the data pattern of the equalization-corrected signal, themeasuring device measuring jitter of the equalization-corrected signal,the adjusting device adjusting the recording condition such that thejitter measured by the measuring device satisfies a desired condition,with reference to the data pattern detected by the detecting device. 21.The recording apparatus according to claim 20, further comprising anadding device for adding a predetermined offset signal to the readsignal, thereby obtaining an offset-added signal, the measuring devicemeasuring the jitter of the offset-added signal.
 22. The recordingapparatus according to claim 15, wherein the measuring device measures,as the jitter, a shift jitter component caused by a state of therecorded data pattern from among the jitter, and the adjusting deviceadjusts the recording condition such that the shift jitter component asthe jitter satisfies the desired condition.
 23. The recording apparatusaccording to claim 22, wherein a state in which the jitter satisfies thedesired condition is a state in which the shift jitter component is lessthan or equal to a first predetermined value.
 24. The informationrecording apparatus according to claim 22, wherein a state in which thejitter satisfies the desired condition is a state in which the shiftjitter components in a plurality of types of respective data patternswith different run lengths are substantially the same to each other. 25.A recording method in a recording apparatus comprising: a recordingdevice for recording a desired data pattern onto a recording mediumcomprising an inner area and a user data area located on an outer sideof the inner area, the recording method comprising: a first calculatingprocess of calculating an optimum power, which is used in recording thedata pattern into a recording-scheduled area portion, before the datapattern is recorded into the recording-scheduled area portion which isan area portion in the user data area in which the data pattern isscheduled to be recorded by the recording device; a first controllingprocess of controlling the recording device to record the data patternwith the optimum power into an area portion which is outer than an endon an outer side of the recording-scheduled area portion; a secondcalculating process of calculating an adjustment power, which is used inadjusting a recording condition of the recording device in an areaportion which is outer than the end on the outer side of therecording-scheduled area portion, in consideration of a differencebetween a recording sensitivity in the recording-scheduled area portionand a recording sensitivity in the area portion which is outer than theend on the outer side of the recording-scheduled area portion, byreading the data pattern recorded by the control of the firstcontrolling process; a second controlling process of controlling therecording device to record the data pattern for adjusting the recordingcondition with the adjustment power into the area portion which is outerthan the end on the outer side of the recording-scheduled area portion;a reading process of reading the data pattern recorded by the control ofthe second controlling process, thereby obtaining a read signal; ameasuring process of measuring jitter of the read signal; an adjustingprocess of adjusting the recording condition such that the jittermeasured by the measuring process satisfies a desired condition; and athird controlling process of controlling the recording device to startthe recording of the data pattern into the recording-scheduled areaportion by using the optimum power and the recording condition adjustedby the adjusting process.
 26. A computer readable recording mediumrecording thereon a computer program for recording control and forcontrolling a computer provided in a recording apparatus comprising: arecording device for recording a desired data pattern onto a recordingmedium comprising an inner area and a user data area located on an outerside of the inner area; a first calculating device for calculating anoptimum power, which is used in recording the data pattern into arecording-scheduled area portion, before the data pattern is recordedinto the recording-scheduled area portion which is an area portion inthe user data area in which the data pattern is scheduled to be recordedby the recording device; a first controlling device for controlling therecording device to record the data pattern with the optimum power intoan area portion which is outer than an end on an outer side of therecording-scheduled area portion; a second calculating device forcalculating an adjustment power, which is used in adjusting a recordingcondition of the recording device in an area portion which is outer thanthe end on the outer side of the recording-scheduled area portion, inconsideration of a difference between a recording sensitivity in therecording-scheduled area portion and a recording sensitivity in the areaportion which is outer than the end on the outer side of therecording-scheduled area portion, by reading the data pattern recordedby the control of the first controlling device; a second controllingdevice for controlling the recording device to record the data patternfor adjusting the recording condition with the adjustment power into thearea portion which is outer than the end on the outer side of therecording-scheduled area portion; a reading device for reading the datapattern recorded by the control of the second controlling device,thereby obtaining a read signal; a measuring device for measuring jitterof the read signal; an adjusting device for adjusting the recordingcondition such that the jitter measured by the measuring devicesatisfies a desired condition; and a third controlling device forcontrolling the recording device to start the recording of the datapattern into the recording-scheduled area portion by using the optimumpower and the recording condition adjusted by the adjusting device, thecomputer program making the computer function as at least one portion ofthe recording device, the first calculating device, the firstcontrolling device, the second calculating device, the secondcontrolling device, the reading device, the measuring device, theadjusting device, and the third controlling device.
 27. A recordingmedium which comprises an inner area and a user data area located on anouter side of the inner area and on which a data pattern is recorded bya recording apparatus comprising: a recording device for recording thedesired data pattern onto the recording medium; a first calculatingdevice for calculating an optimum power, which is used in recording thedata pattern into a recording-scheduled area portion, before the datapattern is recorded into the recording-scheduled area portion which isan area portion in the user data area in which the data pattern isscheduled to be recorded by the recording device; a first controllingdevice for controlling the recording device to record the data patternwith the optimum power into an area portion which is outer than an endon an outer side of the recording-scheduled area portion; a secondcalculating device for calculating an adjustment power, which is used inadjusting a recording condition of the recording device in an areaportion which is outer than the end on the outer side of therecording-scheduled area portion, in consideration of a differencebetween a recording sensitivity in the recording-scheduled area portionand a recording sensitivity in the area portion which is outer than theend on the outer side of the recording-scheduled area portion, byreading the data pattern recorded by the control of the firstcontrolling device; a second controlling device for controlling therecording device to record the data pattern for adjusting the recordingcondition with the adjustment power into the area portion which is outerthan the end on the outer side of the recording-scheduled area portion;a reading device for reading the data pattern recorded by the control ofthe second controlling device, thereby obtaining a read signal; ameasuring device for measuring jitter of the read signal; an adjustingdevice for adjusting the recording condition such that the jittermeasured by the measuring device satisfies a desired condition; and athird controlling device for controlling the recording device to startthe recording of the data pattern into the recording-scheduled areaportion by using the optimum power and the recording condition adjustedby the adjusting device.
 28. A recording medium comprising: an innerarea; a user data area located on an outer side of the inner area; and arecording condition recording area to record therein a recordingcondition adjusted by a recording apparatus comprising: a recordingdevice for recording a desired data pattern onto the recording medium; afirst calculating device for calculating an optimum power, which is usedin recording the data pattern into a recording-scheduled area portion,before the data pattern is recorded into the recording-scheduled areaportion which is an area portion in the user data area in which the datapattern is scheduled to be recorded by the recording device; a firstcontrolling device for controlling the recording device to record thedata pattern with the optimum power into an area portion which is outerthan an end on an outer side of the recording-scheduled area portion; asecond calculating device for calculating an adjustment power, which isused in adjusting the recording condition of the recording device in anarea portion which is outer than the end on the outer side of therecording-scheduled area portion, in consideration of a differencebetween a recording sensitivity in the recording-scheduled area portionand a recording sensitivity in the area portion which is outer than theend on the outer side of the recording-scheduled area portion, byreading the data pattern recorded by the control of the firstcontrolling device; a second controlling device for controlling therecording device to record the data pattern for adjusting the recordingcondition with the adjustment power into the area portion which is outerthan the end on the outer side of the recording-scheduled area portion;a reading device for reading the data pattern recorded by the control ofthe second controlling device, thereby obtaining a read signal; ameasuring device for measuring jitter of the read signal; an adjustingdevice for adjusting the recording condition such that the jittermeasured by the measuring device satisfies a desired condition; and athird controlling device for controlling the recording device to startthe recording of the data pattern into the recording-scheduled areaportion by using the optimum power and the recording condition adjustedby the adjusting device.